| 1 | ;;;; -*- Mode: lisp -*- |
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| 2 | ;;;; |
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| 3 | ;;;; Copyright (c) 2007, 2008, 2011 Raymond Toy |
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| 4 | ;;;; |
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| 5 | ;;;; Permission is hereby granted, free of charge, to any person |
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| 6 | ;;;; obtaining a copy of this software and associated documentation |
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| 7 | ;;;; files (the "Software"), to deal in the Software without |
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| 8 | ;;;; restriction, including without limitation the rights to use, |
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| 9 | ;;;; copy, modify, merge, publish, distribute, sublicense, and/or sell |
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| 10 | ;;;; copies of the Software, and to permit persons to whom the |
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| 11 | ;;;; Software is furnished to do so, subject to the following |
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| 12 | ;;;; conditions: |
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| 13 | ;;;; |
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| 14 | ;;;; The above copyright notice and this permission notice shall be |
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| 15 | ;;;; included in all copies or substantial portions of the Software. |
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| 16 | ;;;; |
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| 17 | ;;;; THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
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| 18 | ;;;; EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES |
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| 19 | ;;;; OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND |
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| 20 | ;;;; NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT |
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| 21 | ;;;; HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, |
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| 22 | ;;;; WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
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| 23 | ;;;; FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR |
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| 24 | ;;;; OTHER DEALINGS IN THE SOFTWARE. |
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| 25 | |
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| 26 | (in-package #:oct) |
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| 27 | |
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| 28 | (defconstant +pi+ |
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| 29 | (make-instance 'qd-real :value octi:+qd-pi+) |
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| 30 | "Pi represented as a QD-REAL") |
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| 31 | |
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| 32 | (defconstant +pi/2+ |
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| 33 | (make-instance 'qd-real :value octi:+qd-pi/2+) |
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| 34 | "Pi/2 represented as a QD-REAL") |
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| 35 | |
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| 36 | (defconstant +pi/4+ |
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| 37 | (make-instance 'qd-real :value octi:+qd-pi/4+) |
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| 38 | "Pi/4 represented as a QD-REAL") |
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| 39 | |
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| 40 | (defconstant +2pi+ |
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| 41 | (make-instance 'qd-real :value octi:+qd-2pi+) |
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| 42 | "2*pi represented as a QD-REAL") |
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| 43 | |
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| 44 | (defconstant +log2+ |
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| 45 | (make-instance 'qd-real :value octi:+qd-log2+) |
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| 46 | "Natural log of 2 represented as a QD-REAL") |
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| 47 | |
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| 48 | ;; How do we represent infinity for a QD-REAL? For now, we just make |
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| 49 | ;; the QD-REAL whose most significant part is infinity. Currently |
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| 50 | ;; only supported on CMUCL. |
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| 51 | #+cmu |
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| 52 | (defconstant +quad-double-float-positive-infinity+ |
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| 53 | (make-instance 'qd-real :value (make-qd-d ext:double-float-positive-infinity)) |
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| 54 | "One representation of positive infinity for QD-REAL") |
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| 55 | |
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| 56 | #+cmu |
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| 57 | (defconstant +quad-double-float-negative-infinity+ |
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| 58 | (make-instance 'qd-real :value (make-qd-d ext:double-float-negative-infinity)) |
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| 59 | "One representation of negative infinity for QD-REAL") |
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| 60 | |
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| 61 | (defconstant +most-positive-quad-double-float+ |
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| 62 | (make-instance 'qd-real |
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| 63 | :value (octi::%make-qd-d most-positive-double-float |
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| 64 | (cl:scale-float most-positive-double-float (cl:* 1 -53)) |
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| 65 | (cl:scale-float most-positive-double-float (cl:* 2 -53)) |
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| 66 | (cl:scale-float most-positive-double-float (cl:* 3 -53)))) |
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| 67 | "Most positive representable QD-REAL") |
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| 68 | |
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| 69 | (defconstant +least-positive-quad-double-float+ |
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| 70 | (make-instance 'qd-real |
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| 71 | :value (make-qd-d least-positive-double-float)) |
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| 72 | "Least positive QD-REAL") |
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| 73 | |
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| 74 | ;; Not sure this is 100% correct, but I think if the first component |
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| 75 | ;; is any smaller than this, the last component would no longer be a |
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| 76 | ;; normalized double-float. |
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| 77 | (defconstant +least-positive-normalized-quad-double-float+ |
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| 78 | (make-instance 'qd-real |
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| 79 | :value (make-qd-d (cl:scale-float least-positive-normalized-double-float (cl:* 3 53)))) |
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| 80 | "Least positive normalized QD-REAL") |
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| 81 | |
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| 82 | (defconstant +qd-real-one+ |
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| 83 | (make-instance 'qd-real :value (make-qd-d 1d0)) |
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| 84 | "QD-REAL representation of 1") |
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| 85 | |
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| 86 | |
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| 87 | (defmethod make-qd ((x cl:rational)) |
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| 88 | ;; We should do something better than this. |
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| 89 | (make-instance 'qd-real :value (rational-to-qd x))) |
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| 90 | |
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| 91 | |
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| 92 | (defmethod add1 ((a number)) |
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| 93 | (cl::1+ a)) |
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| 94 | |
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| 95 | (defmethod add1 ((a qd-real)) |
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| 96 | (make-instance 'qd-real :value (add-qd-d (qd-value a) 1d0))) |
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| 97 | |
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| 98 | (defmethod sub1 ((a number)) |
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| 99 | (cl::1- a)) |
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| 100 | |
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| 101 | (defmethod sub1 ((a qd-real)) |
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| 102 | (make-instance 'qd-real :value (sub-qd-d (qd-value a) 1d0))) |
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| 103 | |
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| 104 | (declaim (inline 1+ 1-)) |
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| 105 | |
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| 106 | (defun 1+ (x) |
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| 107 | (add1 x)) |
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| 108 | |
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| 109 | (defun 1- (x) |
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| 110 | (sub1 x)) |
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| 111 | |
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| 112 | (defmethod two-arg-+ ((a qd-real) (b qd-real)) |
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| 113 | (make-instance 'qd-real :value (add-qd (qd-value a) (qd-value b)))) |
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| 114 | |
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| 115 | (defmethod two-arg-+ ((a qd-real) (b cl:float)) |
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| 116 | (make-instance 'qd-real :value (add-qd-d (qd-value a) (cl:float b 1d0)))) |
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| 117 | |
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| 118 | #+cmu |
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| 119 | (defmethod two-arg-+ ((a qd-real) (b ext:double-double-float)) |
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| 120 | (make-instance 'qd-real :value (add-qd-dd (qd-value a) b))) |
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| 121 | |
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| 122 | (defmethod two-arg-+ ((a real) (b qd-real)) |
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| 123 | (+ b a)) |
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| 124 | |
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| 125 | (defmethod two-arg-+ ((a number) (b number)) |
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| 126 | (cl:+ a b)) |
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| 127 | |
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| 128 | (defun + (&rest args) |
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| 129 | (if (null args) |
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| 130 | 0 |
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| 131 | (do ((args (cdr args) (cdr args)) |
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| 132 | (res (car args) |
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| 133 | (two-arg-+ res (car args)))) |
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| 134 | ((null args) res)))) |
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| 135 | |
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| 136 | (defmethod two-arg-- ((a qd-real) (b qd-real)) |
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| 137 | (make-instance 'qd-real :value (sub-qd (qd-value a) (qd-value b)))) |
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| 138 | |
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| 139 | (defmethod two-arg-- ((a qd-real) (b cl:float)) |
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| 140 | (make-instance 'qd-real :value (sub-qd-d (qd-value a) (cl:float b 1d0)))) |
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| 141 | |
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| 142 | #+cmu |
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| 143 | (defmethod two-arg-- ((a qd-real) (b ext:double-double-float)) |
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| 144 | (make-instance 'qd-real :value (sub-qd-dd (qd-value a) b))) |
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| 145 | |
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| 146 | (defmethod two-arg-- ((a cl:float) (b qd-real)) |
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| 147 | (make-instance 'qd-real :value (sub-d-qd (cl:float a 1d0) (qd-value b)))) |
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| 148 | |
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| 149 | (defmethod two-arg-- ((a number) (b number)) |
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| 150 | (cl:- a b)) |
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| 151 | |
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| 152 | (defmethod unary-minus ((a number)) |
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| 153 | (cl:- a)) |
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| 154 | |
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| 155 | (defmethod unary-minus ((a qd-real)) |
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| 156 | (make-instance 'qd-real :value (neg-qd (qd-value a)))) |
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| 157 | |
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| 158 | (defun - (number &rest more-numbers) |
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| 159 | (if more-numbers |
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| 160 | (do ((nlist more-numbers (cdr nlist)) |
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| 161 | (result number)) |
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| 162 | ((atom nlist) result) |
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| 163 | (declare (list nlist)) |
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| 164 | (setq result (two-arg-- result (car nlist)))) |
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| 165 | (unary-minus number))) |
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| 166 | |
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| 167 | |
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| 168 | (defmethod two-arg-* ((a qd-real) (b qd-real)) |
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| 169 | (make-instance 'qd-real :value (mul-qd (qd-value a) (qd-value b)))) |
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| 170 | |
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| 171 | (defmethod two-arg-* ((a qd-real) (b cl:float)) |
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| 172 | (make-instance 'qd-real :value (mul-qd-d (qd-value a) (cl:float b 1d0)))) |
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| 173 | |
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| 174 | #+cmu |
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| 175 | (defmethod two-arg-* ((a qd-real) (b ext:double-double-float)) |
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| 176 | ;; We'd normally want to use mul-qd-dd, but mul-qd-dd is broken. |
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| 177 | (make-instance 'qd-real :value (mul-qd (qd-value a) |
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| 178 | (make-qd-dd b 0w0)))) |
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| 179 | |
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| 180 | (defmethod two-arg-* ((a real) (b qd-real)) |
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| 181 | (* b a)) |
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| 182 | |
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| 183 | (defmethod two-arg-* ((a number) (b number)) |
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| 184 | (cl:* a b)) |
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| 185 | |
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| 186 | (defun * (&rest args) |
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| 187 | (if (null args) |
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| 188 | 1 |
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| 189 | (do ((args (cdr args) (cdr args)) |
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| 190 | (res (car args) |
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| 191 | (two-arg-* res (car args)))) |
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| 192 | ((null args) res)))) |
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| 193 | |
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| 194 | (defmethod two-arg-/ ((a qd-real) (b qd-real)) |
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| 195 | (make-instance 'qd-real :value (div-qd (qd-value a) (qd-value b)))) |
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| 196 | |
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| 197 | (defmethod two-arg-/ ((a qd-real) (b cl:float)) |
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| 198 | (make-instance 'qd-real :value (div-qd-d (qd-value a) (cl:float b 1d0)))) |
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| 199 | |
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| 200 | #+cmu |
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| 201 | (defmethod two-arg-/ ((a qd-real) (b ext:double-double-float)) |
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| 202 | (make-instance 'qd-real :value (div-qd-dd (qd-value a) |
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| 203 | b))) |
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| 204 | |
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| 205 | (defmethod two-arg-/ ((a cl:float) (b qd-real)) |
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| 206 | (make-instance 'qd-real :value (div-qd (make-qd-d (cl:float a 1d0)) |
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| 207 | (qd-value b)))) |
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| 208 | |
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| 209 | #+cmu |
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| 210 | (defmethod two-arg-/ ((a ext:double-double-float) (b qd-real)) |
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| 211 | (make-instance 'qd-real :value (div-qd (make-qd-dd a 0w0) |
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| 212 | (qd-value b)))) |
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| 213 | |
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| 214 | (defmethod two-arg-/ ((a number) (b number)) |
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| 215 | (cl:/ a b)) |
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| 216 | |
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| 217 | (defmethod unary-divide ((a number)) |
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| 218 | (cl:/ a)) |
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| 219 | |
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| 220 | (defmethod unary-divide ((a qd-real)) |
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| 221 | (make-instance 'qd-real :value (div-qd +qd-one+ (qd-value a)))) |
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| 222 | |
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| 223 | (defun / (number &rest more-numbers) |
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| 224 | (if more-numbers |
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| 225 | (do ((nlist more-numbers (cdr nlist)) |
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| 226 | (result number)) |
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| 227 | ((atom nlist) result) |
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| 228 | (declare (list nlist)) |
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| 229 | (setq result (two-arg-/ result (car nlist)))) |
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| 230 | (unary-divide number))) |
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| 231 | |
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| 232 | (macrolet ((frob (name &optional (type 'real)) |
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| 233 | (let ((method-name (intern (concatenate 'string |
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| 234 | (string '#:q) |
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| 235 | (symbol-name name)))) |
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| 236 | (cl-name (intern (symbol-name name) :cl)) |
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| 237 | (qd-name (intern (concatenate 'string |
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| 238 | (symbol-name name) |
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| 239 | (string '#:-qd))))) |
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| 240 | `(progn |
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| 241 | (defmethod ,method-name ((x ,type)) |
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| 242 | (,cl-name x)) |
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| 243 | (defmethod ,method-name ((x qd-real)) |
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| 244 | (,qd-name (qd-value x))) |
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| 245 | (declaim (inline ,name)) |
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| 246 | (defun ,name (x) |
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| 247 | (,method-name x)))))) |
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| 248 | (frob zerop number) |
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| 249 | (frob plusp) |
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| 250 | (frob minusp)) |
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| 251 | |
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| 252 | (defun bignum-to-qd (bignum) |
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| 253 | (make-instance 'qd-real |
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| 254 | :value (rational-to-qd bignum))) |
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| 255 | |
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| 256 | (defmethod qfloat ((x real) (num-type cl:float)) |
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| 257 | (cl:float x num-type)) |
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| 258 | |
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| 259 | (defmethod qfloat ((x cl:float) (num-type qd-real)) |
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| 260 | (make-instance 'qd-real :value (make-qd-d (cl:float x 1d0)))) |
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| 261 | |
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| 262 | (defmethod qfloat ((x integer) (num-type qd-real)) |
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| 263 | (cond ((typep x 'fixnum) |
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| 264 | (make-instance 'qd-real :value (make-qd-d (cl:float x 1d0)))) |
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| 265 | (t |
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| 266 | ;; A bignum |
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| 267 | (bignum-to-qd x)))) |
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| 268 | |
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| 269 | #+nil |
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| 270 | (defmethod qfloat ((x ratio) (num-type qd-real)) |
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| 271 | ;; This probably has some issues with roundoff |
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| 272 | (two-arg-/ (qfloat (numerator x) num-type) |
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| 273 | (qfloat (denominator x) num-type))) |
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| 274 | |
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| 275 | (defmethod qfloat ((x ratio) (num-type qd-real)) |
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| 276 | (make-instance 'qd-real :value (rational-to-qd x))) |
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| 277 | |
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| 278 | #+cmu |
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| 279 | (defmethod qfloat ((x ext:double-double-float) (num-type qd-real)) |
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| 280 | (make-instance 'qd-real :value (make-qd-dd x 0w0))) |
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| 281 | |
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| 282 | (defmethod qfloat ((x qd-real) (num-type cl:float)) |
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| 283 | (multiple-value-bind (q0 q1 q2 q3) |
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| 284 | (qd-parts (qd-value x)) |
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| 285 | (cl:float (cl:+ q0 q1 q2 q3) num-type))) |
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| 286 | |
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| 287 | #+cmu |
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| 288 | (defmethod qfloat ((x qd-real) (num-type ext:double-double-float)) |
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| 289 | (multiple-value-bind (q0 q1 q2 q3) |
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| 290 | (qd-parts (qd-value x)) |
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| 291 | (cl:+ (cl:float q0 1w0) |
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| 292 | (cl:float q1 1w0) |
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| 293 | (cl:float q2 1w0) |
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| 294 | (cl:float q3 1w0)))) |
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| 295 | |
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| 296 | (defmethod qfloat ((x qd-real) (num-type qd-real)) |
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| 297 | x) |
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| 298 | |
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| 299 | (declaim (inline float)) |
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| 300 | (defun float (x num-type) |
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| 301 | (qfloat x num-type)) |
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| 302 | |
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| 303 | (defmethod qrealpart ((x number)) |
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| 304 | (cl:realpart x)) |
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| 305 | (defmethod qrealpart ((x qd-real)) |
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| 306 | x) |
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| 307 | (defmethod qrealpart ((x qd-complex)) |
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| 308 | (make-instance 'qd-real :value (qd-real x))) |
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| 309 | (defun realpart (x) |
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| 310 | (qrealpart x)) |
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| 311 | |
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| 312 | (defmethod qimagpart ((x number)) |
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| 313 | (cl:imagpart x)) |
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| 314 | (defmethod qimagpart ((x qd-real)) |
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| 315 | (make-qd 0d0)) |
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| 316 | (defmethod qimagpart ((x qd-complex)) |
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| 317 | (make-instance 'qd-real :value (qd-imag x))) |
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| 318 | |
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| 319 | (defun imagpart (x) |
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| 320 | (qimagpart x)) |
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| 321 | |
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| 322 | (defmethod qconjugate ((a number)) |
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| 323 | (cl:conjugate a)) |
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| 324 | |
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| 325 | (defmethod qconjugate ((a qd-real)) |
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| 326 | (make-instance 'qd-real :value (qd-value a))) |
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| 327 | |
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| 328 | (defmethod qconjugate ((a qd-complex)) |
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| 329 | (make-instance 'qd-complex |
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| 330 | :real (qd-real a) |
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| 331 | :imag (neg-qd (qd-imag a)))) |
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| 332 | |
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| 333 | (defun conjugate (z) |
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| 334 | (qconjugate z)) |
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| 335 | |
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| 336 | (defmethod qscale-float ((f cl:float) (n integer)) |
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| 337 | (cl:scale-float f n)) |
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| 338 | |
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| 339 | (defmethod qscale-float ((f qd-real) (n integer)) |
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| 340 | (make-instance 'qd-real :value (scale-float-qd (qd-value f) n))) |
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| 341 | |
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| 342 | (declaim (inline scale-float)) |
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| 343 | (defun scale-float (f n) |
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| 344 | (qscale-float f n)) |
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| 345 | |
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| 346 | (macrolet |
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| 347 | ((frob (op) |
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| 348 | (let ((method (intern (concatenate 'string |
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| 349 | (string '#:two-arg-) |
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| 350 | (symbol-name op)))) |
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| 351 | (cl-fun (find-symbol (symbol-name op) :cl)) |
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| 352 | (qd-fun (intern (concatenate 'string (string '#:qd-) (symbol-name op)) |
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| 353 | '#:octi))) |
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| 354 | `(progn |
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| 355 | (defmethod ,method ((a real) (b real)) |
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| 356 | (,cl-fun a b)) |
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| 357 | (defmethod ,method ((a qd-real) (b real)) |
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| 358 | (,qd-fun (qd-value a) (make-qd-d (cl:float b 1d0)))) |
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| 359 | (defmethod ,method ((a real) (b qd-real)) |
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| 360 | ;; This is not really right if A is a rational. We're |
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| 361 | ;; supposed to compare them as rationals. |
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| 362 | (,qd-fun (make-qd-d (cl:float a 1d0)) (qd-value b))) |
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| 363 | (defmethod ,method ((a qd-real) (b qd-real)) |
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| 364 | (,qd-fun (qd-value a) (qd-value b))) |
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| 365 | (defun ,op (number &rest more-numbers) |
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| 366 | "Returns T if its arguments are in strictly increasing order, NIL otherwise." |
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| 367 | (declare (optimize (safety 2)) |
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| 368 | (dynamic-extent more-numbers)) |
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| 369 | (do* ((n number (car nlist)) |
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| 370 | (nlist more-numbers (cdr nlist))) |
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| 371 | ((atom nlist) t) |
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| 372 | (declare (list nlist)) |
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| 373 | (if (not (,method n (car nlist))) (return nil)))))))) |
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| 374 | (frob <) |
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| 375 | (frob >) |
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| 376 | (frob <=) |
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| 377 | (frob >=)) |
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| 378 | |
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| 379 | ;; Handle the special functions for a real argument. Complex args are |
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| 380 | ;; handled elsewhere. |
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| 381 | (macrolet |
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| 382 | ((frob (name) |
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| 383 | (let ((method-name |
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| 384 | (intern (concatenate 'string (string '#:q) |
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| 385 | (symbol-name name)))) |
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| 386 | (cl-name (intern (symbol-name name) :cl)) |
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| 387 | (qd-name (intern (concatenate 'string (symbol-name name) |
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| 388 | (string '#:-qd))))) |
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| 389 | `(progn |
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| 390 | (defmethod ,name ((x number)) |
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| 391 | (,cl-name x)) |
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| 392 | (defmethod ,name ((x qd-real)) |
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| 393 | (make-instance 'qd-real :value (,qd-name (qd-value x)))))))) |
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| 394 | (frob abs) |
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| 395 | (frob exp) |
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| 396 | (frob sin) |
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| 397 | (frob cos) |
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| 398 | (frob tan) |
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| 399 | ;;(frob asin) |
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| 400 | ;;(frob acos) |
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| 401 | (frob sinh) |
|---|
| 402 | (frob cosh) |
|---|
| 403 | (frob tanh) |
|---|
| 404 | (frob asinh) |
|---|
| 405 | ;;(frob acosh) |
|---|
| 406 | ;;(frob atanh) |
|---|
| 407 | ) |
|---|
| 408 | |
|---|
| 409 | (defmethod sqrt ((x number)) |
|---|
| 410 | (cl:sqrt x)) |
|---|
| 411 | |
|---|
| 412 | (defmethod sqrt ((x qd-real)) |
|---|
| 413 | (if (minusp x) |
|---|
| 414 | (make-instance 'qd-complex |
|---|
| 415 | :real +qd-zero+ |
|---|
| 416 | :imag (sqrt-qd (neg-qd (qd-value x)))) |
|---|
| 417 | (make-instance 'qd-real :value (sqrt-qd (qd-value x))))) |
|---|
| 418 | |
|---|
| 419 | (defun scalb (x n) |
|---|
| 420 | "Compute 2^N * X without compute 2^N first (use properties of the |
|---|
| 421 | underlying floating-point format" |
|---|
| 422 | (declare (type qd-real x)) |
|---|
| 423 | (scale-float x n)) |
|---|
| 424 | |
|---|
| 425 | (declaim (inline qd-cssqs)) |
|---|
| 426 | (defun qd-cssqs (z) |
|---|
| 427 | (multiple-value-bind (rho k) |
|---|
| 428 | (octi::hypot-aux-qd (qd-value (realpart z)) |
|---|
| 429 | (qd-value (imagpart z))) |
|---|
| 430 | (values (make-instance 'qd-real :value rho) |
|---|
| 431 | k))) |
|---|
| 432 | |
|---|
| 433 | #+nil |
|---|
| 434 | (defmethod qabs ((z qd-complex)) |
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| 435 | ;; sqrt(x^2+y^2) |
|---|
| 436 | ;; If |x| > |y| then sqrt(x^2+y^2) = |x|*sqrt(1+(y/x)^2) |
|---|
| 437 | (multiple-value-bind (abs^2 rho) |
|---|
| 438 | (hypot-qd (qd-value (realpart z)) |
|---|
| 439 | (qd-value (imagpart z))) |
|---|
| 440 | (scale-float (make-instance 'qd-real :value (sqrt abs^2)) |
|---|
| 441 | rho))) |
|---|
| 442 | |
|---|
| 443 | (defmethod abs ((z qd-complex)) |
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| 444 | ;; sqrt(x^2+y^2) |
|---|
| 445 | ;; If |x| > |y| then sqrt(x^2+y^2) = |x|*sqrt(1+(y/x)^2) |
|---|
| 446 | (make-instance 'qd-real |
|---|
| 447 | :value (hypot-qd (qd-value (realpart z)) |
|---|
| 448 | (qd-value (imagpart z))))) |
|---|
| 449 | |
|---|
| 450 | (defmethod log ((a number) &optional b) |
|---|
| 451 | (if b |
|---|
| 452 | (cl:log a b) |
|---|
| 453 | (cl:log a))) |
|---|
| 454 | |
|---|
| 455 | (defmethod log ((a qd-real) &optional b) |
|---|
| 456 | (if b |
|---|
| 457 | (/ (log a) (log b)) |
|---|
| 458 | (if (minusp (float-sign a)) |
|---|
| 459 | (make-instance 'qd-complex |
|---|
| 460 | :real (log-qd (abs-qd (qd-value a))) |
|---|
| 461 | :imag +qd-pi+) |
|---|
| 462 | (make-instance 'qd-real :value (log-qd (qd-value a)))))) |
|---|
| 463 | |
|---|
| 464 | (defmethod log1p ((a qd-real)) |
|---|
| 465 | (make-instance 'qd-real :value (log1p-qd (qd-value a)))) |
|---|
| 466 | |
|---|
| 467 | (defmethod atan ((y real) &optional x) |
|---|
| 468 | (cond (x |
|---|
| 469 | (cond ((typep x 'qd-real) |
|---|
| 470 | (make-instance 'qd-real |
|---|
| 471 | :value (atan2-qd (qd-value y) (qd-value x)))) |
|---|
| 472 | (t |
|---|
| 473 | (cl:atan y x)))) |
|---|
| 474 | (t |
|---|
| 475 | (cl:atan y)))) |
|---|
| 476 | |
|---|
| 477 | (defmethod atan ((y qd-real) &optional x) |
|---|
| 478 | (make-instance 'qd-real |
|---|
| 479 | :value |
|---|
| 480 | (if x |
|---|
| 481 | (atan2-qd (qd-value y) (qd-value x)) |
|---|
| 482 | (atan-qd (qd-value y))))) |
|---|
| 483 | |
|---|
| 484 | (defmethod qexpt ((x number) (y number)) |
|---|
| 485 | (cl:expt x y)) |
|---|
| 486 | |
|---|
| 487 | (defmethod qexpt ((x qd-real) (y real)) |
|---|
| 488 | (exp (* y (log x)))) |
|---|
| 489 | |
|---|
| 490 | (defmethod qexpt ((x real) (y qd-real)) |
|---|
| 491 | (exp (* y (log x)))) |
|---|
| 492 | |
|---|
| 493 | (defmethod qexpt ((x qd-real) (y cl:complex)) |
|---|
| 494 | (exp (* (make-instance 'qd-complex |
|---|
| 495 | :real (qd-value (realpart y)) |
|---|
| 496 | :imag (qd-value (imagpart y))) |
|---|
| 497 | (log x)))) |
|---|
| 498 | |
|---|
| 499 | (defmethod qexpt ((x cl:complex) (y qd-real)) |
|---|
| 500 | (exp (* y |
|---|
| 501 | (log (make-instance 'qd-complex |
|---|
| 502 | :real (qd-value (realpart x)) |
|---|
| 503 | :imag (qd-value (imagpart x))))))) |
|---|
| 504 | |
|---|
| 505 | (defmethod qexpt ((x qd-real) (y qd-real)) |
|---|
| 506 | ;; x^y = exp(y*log(x)) |
|---|
| 507 | (exp (* y (log x)))) |
|---|
| 508 | |
|---|
| 509 | (defmethod qexpt ((x qd-real) (y integer)) |
|---|
| 510 | (make-instance 'qd-real |
|---|
| 511 | :value (npow (qd-value x) y))) |
|---|
| 512 | |
|---|
| 513 | (declaim (inline expt)) |
|---|
| 514 | (defun expt (x y) |
|---|
| 515 | (qexpt x y)) |
|---|
| 516 | |
|---|
| 517 | |
|---|
| 518 | |
|---|
| 519 | (defmethod two-arg-= ((a number) (b number)) |
|---|
| 520 | (cl:= a b)) |
|---|
| 521 | |
|---|
| 522 | (defmethod two-arg-= ((a qd-real) (b number)) |
|---|
| 523 | (if (cl:realp b) |
|---|
| 524 | (qd-= (qd-value a) (make-qd-d (cl:float b 1d0))) |
|---|
| 525 | nil)) |
|---|
| 526 | |
|---|
| 527 | (defmethod two-arg-= ((a number) (b qd-real)) |
|---|
| 528 | (if (cl:realp a) |
|---|
| 529 | (qd-= (make-qd-d (cl:float a 1d0)) (qd-value b)) |
|---|
| 530 | nil)) |
|---|
| 531 | |
|---|
| 532 | (defmethod two-arg-= ((a qd-complex) b) |
|---|
| 533 | (and (two-arg-= (realpart a) (realpart b)) |
|---|
| 534 | (two-arg-= (imagpart a) (imagpart b)))) |
|---|
| 535 | |
|---|
| 536 | (defmethod two-arg-= (a (b qd-complex)) |
|---|
| 537 | (and (two-arg-= (realpart a) (realpart b)) |
|---|
| 538 | (two-arg-= (imagpart a) (imagpart b)))) |
|---|
| 539 | |
|---|
| 540 | |
|---|
| 541 | (defmethod two-arg-= ((a qd-real) (b qd-real)) |
|---|
| 542 | (qd-= (qd-value a) (qd-value b))) |
|---|
| 543 | |
|---|
| 544 | (defun = (number &rest more-numbers) |
|---|
| 545 | "Returns T if all of its arguments are numerically equal, NIL otherwise." |
|---|
| 546 | (declare (optimize (safety 2)) |
|---|
| 547 | (dynamic-extent more-numbers)) |
|---|
| 548 | (do ((nlist more-numbers (cdr nlist))) |
|---|
| 549 | ((atom nlist) t) |
|---|
| 550 | (declare (list nlist)) |
|---|
| 551 | (if (not (two-arg-= (car nlist) number)) |
|---|
| 552 | (return nil)))) |
|---|
| 553 | |
|---|
| 554 | (defun /= (number &rest more-numbers) |
|---|
| 555 | "Returns T if no two of its arguments are numerically equal, NIL otherwise." |
|---|
| 556 | (declare (optimize (safety 2)) |
|---|
| 557 | (dynamic-extent more-numbers)) |
|---|
| 558 | (do* ((head number (car nlist)) |
|---|
| 559 | (nlist more-numbers (cdr nlist))) |
|---|
| 560 | ((atom nlist) t) |
|---|
| 561 | (declare (list nlist)) |
|---|
| 562 | (unless (do* ((nl nlist (cdr nl))) |
|---|
| 563 | ((atom nl) t) |
|---|
| 564 | (declare (list nl)) |
|---|
| 565 | (if (two-arg-= head (car nl)) |
|---|
| 566 | (return nil))) |
|---|
| 567 | (return nil)))) |
|---|
| 568 | |
|---|
| 569 | (defmethod qcomplex ((x real) &optional y) |
|---|
| 570 | (cl:complex x (if y y 0))) |
|---|
| 571 | |
|---|
| 572 | (defmethod qcomplex ((x qd-real) &optional y) |
|---|
| 573 | (make-instance 'qd-complex |
|---|
| 574 | :real (qd-value x) |
|---|
| 575 | :imag (if y (qd-value y) +qd-zero+))) |
|---|
| 576 | |
|---|
| 577 | (defun complex (x &optional (y 0)) |
|---|
| 578 | (qcomplex x y)) |
|---|
| 579 | |
|---|
| 580 | (defmethod qinteger-decode-float ((f cl:float)) |
|---|
| 581 | (cl:integer-decode-float f)) |
|---|
| 582 | |
|---|
| 583 | (defmethod qinteger-decode-float ((f qd-real)) |
|---|
| 584 | (integer-decode-qd (qd-value f))) |
|---|
| 585 | |
|---|
| 586 | (declaim (inline integer-decode-float)) |
|---|
| 587 | (defun integer-decode-float (f) |
|---|
| 588 | (qinteger-decode-float f)) |
|---|
| 589 | |
|---|
| 590 | (defmethod qdecode-float ((f cl:float)) |
|---|
| 591 | (cl:decode-float f)) |
|---|
| 592 | |
|---|
| 593 | (defmethod qdecode-float ((f qd-real)) |
|---|
| 594 | (multiple-value-bind (frac exp s) |
|---|
| 595 | (decode-float-qd (qd-value f)) |
|---|
| 596 | (values (make-instance 'qd-real :value frac) |
|---|
| 597 | exp |
|---|
| 598 | (make-instance 'qd-real :value s)))) |
|---|
| 599 | |
|---|
| 600 | (declaim (inline decode-float)) |
|---|
| 601 | (defun decode-float (f) |
|---|
| 602 | (qdecode-float f)) |
|---|
| 603 | |
|---|
| 604 | (defmethod qfloor ((x real) &optional y) |
|---|
| 605 | (if y |
|---|
| 606 | (cl:floor x y) |
|---|
| 607 | (cl:floor x))) |
|---|
| 608 | |
|---|
| 609 | (defmethod qfloor ((x qd-real) &optional y) |
|---|
| 610 | (if (and y (/= y 1)) |
|---|
| 611 | (let ((f (qfloor (/ x y)))) |
|---|
| 612 | (values f |
|---|
| 613 | (- x (* f y)))) |
|---|
| 614 | (let ((f (ffloor-qd (qd-value x)))) |
|---|
| 615 | (multiple-value-bind (int exp sign) |
|---|
| 616 | (integer-decode-qd f) |
|---|
| 617 | (values (ash (* sign int) exp) |
|---|
| 618 | (make-instance 'qd-real |
|---|
| 619 | :value (qd-value |
|---|
| 620 | (- x (make-instance 'qd-real |
|---|
| 621 | :value f))))))))) |
|---|
| 622 | |
|---|
| 623 | (defun floor (x &optional y) |
|---|
| 624 | (qfloor x y)) |
|---|
| 625 | |
|---|
| 626 | (defmethod qffloor ((x real) &optional y) |
|---|
| 627 | (if y |
|---|
| 628 | (cl:ffloor x y) |
|---|
| 629 | (cl:ffloor x))) |
|---|
| 630 | |
|---|
| 631 | (defmethod qffloor ((x qd-real) &optional y) |
|---|
| 632 | (if (and y (/= y 1)) |
|---|
| 633 | (let ((f (qffloor (/ x y)))) |
|---|
| 634 | (values f |
|---|
| 635 | (- x (* f y)))) |
|---|
| 636 | (let ((f (make-instance 'qd-real :value (ffloor-qd (qd-value x))))) |
|---|
| 637 | (values f |
|---|
| 638 | (- x f))))) |
|---|
| 639 | |
|---|
| 640 | (defun ffloor (x &optional y) |
|---|
| 641 | (qffloor x y)) |
|---|
| 642 | |
|---|
| 643 | (defun ceiling (x &optional y) |
|---|
| 644 | (multiple-value-bind (f rem) |
|---|
| 645 | (floor x y) |
|---|
| 646 | (if (zerop rem) |
|---|
| 647 | (values (+ f 1) |
|---|
| 648 | rem) |
|---|
| 649 | (values (+ f 1) |
|---|
| 650 | (- rem 1))))) |
|---|
| 651 | |
|---|
| 652 | (defun fceiling (x &optional y) |
|---|
| 653 | (multiple-value-bind (f rem) |
|---|
| 654 | (ffloor x y) |
|---|
| 655 | (if (zerop rem) |
|---|
| 656 | (values (+ f 1) |
|---|
| 657 | rem) |
|---|
| 658 | (values (+ f 1) |
|---|
| 659 | (- rem 1))))) |
|---|
| 660 | |
|---|
| 661 | (defun truncate (x &optional (y 1)) |
|---|
| 662 | (if (minusp x) |
|---|
| 663 | (ceiling x y) |
|---|
| 664 | (floor x y))) |
|---|
| 665 | |
|---|
| 666 | (defun ftruncate (x &optional (y 1)) |
|---|
| 667 | (if (minusp x) |
|---|
| 668 | (fceiling x y) |
|---|
| 669 | (ffloor x y))) |
|---|
| 670 | |
|---|
| 671 | (defmethod %unary-round ((x real)) |
|---|
| 672 | (cl::round x)) |
|---|
| 673 | |
|---|
| 674 | (defmethod %unary-round ((number qd-real)) |
|---|
| 675 | (multiple-value-bind (bits exp) |
|---|
| 676 | (integer-decode-float number) |
|---|
| 677 | (let* ((shifted (ash bits exp)) |
|---|
| 678 | (rounded (if (and (minusp exp) |
|---|
| 679 | (oddp shifted) |
|---|
| 680 | (not (zerop (logand bits |
|---|
| 681 | (ash 1 (- -1 exp)))))) |
|---|
| 682 | (1+ shifted) |
|---|
| 683 | shifted))) |
|---|
| 684 | (if (minusp number) |
|---|
| 685 | (- rounded) |
|---|
| 686 | rounded)))) |
|---|
| 687 | |
|---|
| 688 | (defun round (number &optional (divisor 1)) |
|---|
| 689 | (if (eql divisor 1) |
|---|
| 690 | (let ((r (%unary-round number))) |
|---|
| 691 | (values r |
|---|
| 692 | (- number r))) |
|---|
| 693 | (multiple-value-bind (tru rem) |
|---|
| 694 | (truncate number divisor) |
|---|
| 695 | (if (zerop rem) |
|---|
| 696 | (values tru rem) |
|---|
| 697 | (let ((thresh (/ (abs divisor) 2))) |
|---|
| 698 | (cond ((or (> rem thresh) |
|---|
| 699 | (and (= rem thresh) (oddp tru))) |
|---|
| 700 | (if (minusp divisor) |
|---|
| 701 | (values (- tru 1) (+ rem divisor)) |
|---|
| 702 | (values (+ tru 1) (- rem divisor)))) |
|---|
| 703 | ((let ((-thresh (- thresh))) |
|---|
| 704 | (or (< rem -thresh) |
|---|
| 705 | (and (= rem -thresh) (oddp tru)))) |
|---|
| 706 | (if (minusp divisor) |
|---|
| 707 | (values (+ tru 1) (- rem divisor)) |
|---|
| 708 | (values (- tru 1) (+ rem divisor)))) |
|---|
| 709 | (t (values tru rem)))))))) |
|---|
| 710 | |
|---|
| 711 | (defun fround (number &optional (divisor 1)) |
|---|
| 712 | "Same as ROUND, but returns first value as a float." |
|---|
| 713 | (multiple-value-bind (res rem) |
|---|
| 714 | (round number divisor) |
|---|
| 715 | (values (float res (if (floatp rem) rem 1.0)) rem))) |
|---|
| 716 | |
|---|
| 717 | (defmethod qfloat-sign ((a real) &optional (f (float 1 a))) |
|---|
| 718 | (cl:float-sign a f)) |
|---|
| 719 | |
|---|
| 720 | |
|---|
| 721 | (defmethod qfloat-sign ((a qd-real) &optional f) |
|---|
| 722 | (if f |
|---|
| 723 | (make-instance 'qd-real |
|---|
| 724 | :value (mul-qd-d (abs-qd (qd-value f)) |
|---|
| 725 | (cl:float-sign (qd-0 (qd-value a))))) |
|---|
| 726 | (make-instance 'qd-real :value (make-qd-d (cl:float-sign (qd-0 (qd-value a))))))) |
|---|
| 727 | |
|---|
| 728 | (declaim (inline float-sign)) |
|---|
| 729 | (defun float-sign (n &optional (float2 nil float2p)) |
|---|
| 730 | (if float2p |
|---|
| 731 | (qfloat-sign n float2) |
|---|
| 732 | (qfloat-sign n))) |
|---|
| 733 | |
|---|
| 734 | (defun max (number &rest more-numbers) |
|---|
| 735 | "Returns the greatest of its arguments." |
|---|
| 736 | (declare (optimize (safety 2)) (type (or real qd-real) number) |
|---|
| 737 | (dynamic-extent more-numbers)) |
|---|
| 738 | (dolist (real more-numbers) |
|---|
| 739 | (when (> real number) |
|---|
| 740 | (setq number real))) |
|---|
| 741 | number) |
|---|
| 742 | |
|---|
| 743 | (defun min (number &rest more-numbers) |
|---|
| 744 | "Returns the least of its arguments." |
|---|
| 745 | (declare (optimize (safety 2)) (type (or real qd-real) number) |
|---|
| 746 | (dynamic-extent more-numbers)) |
|---|
| 747 | (do ((nlist more-numbers (cdr nlist)) |
|---|
| 748 | (result (the (or real qd-real) number))) |
|---|
| 749 | ((null nlist) (return result)) |
|---|
| 750 | (declare (list nlist)) |
|---|
| 751 | (if (< (car nlist) result) |
|---|
| 752 | (setq result (car nlist))))) |
|---|
| 753 | |
|---|
| 754 | (defmethod asin ((x number)) |
|---|
| 755 | (cl:asin x)) |
|---|
| 756 | |
|---|
| 757 | (defmethod asin ((x qd-real)) |
|---|
| 758 | (if (<= -1 x 1) |
|---|
| 759 | (make-instance 'qd-real :value (asin-qd (qd-value x))) |
|---|
| 760 | (qd-complex-asin x))) |
|---|
| 761 | |
|---|
| 762 | (defmethod acos ((x number)) |
|---|
| 763 | (cl:acos x)) |
|---|
| 764 | |
|---|
| 765 | (defmethod acos ((x qd-real)) |
|---|
| 766 | (cond ((> (abs x) 1) |
|---|
| 767 | (qd-complex-acos x)) |
|---|
| 768 | (t |
|---|
| 769 | (make-instance 'qd-real :value (acos-qd (qd-value x)))))) |
|---|
| 770 | |
|---|
| 771 | (defmethod acosh ((x number)) |
|---|
| 772 | (cl:acosh x)) |
|---|
| 773 | |
|---|
| 774 | (defmethod acosh ((x qd-real)) |
|---|
| 775 | (if (< x 1) |
|---|
| 776 | (qd-complex-acosh x) |
|---|
| 777 | (make-instance 'qd-real :value (acosh-qd (qd-value x))))) |
|---|
| 778 | |
|---|
| 779 | (defmethod atanh ((x number)) |
|---|
| 780 | (cl:atanh x)) |
|---|
| 781 | |
|---|
| 782 | (defmethod atanh ((x qd-real)) |
|---|
| 783 | (if (> (abs x) 1) |
|---|
| 784 | (qd-complex-atanh x) |
|---|
| 785 | (make-instance 'qd-real :value (atanh-qd (qd-value x))))) |
|---|
| 786 | |
|---|
| 787 | (defmethod cis ((x real)) |
|---|
| 788 | (cl:cis x)) |
|---|
| 789 | |
|---|
| 790 | (defmethod cis ((x qd-real)) |
|---|
| 791 | (multiple-value-bind (s c) |
|---|
| 792 | (sincos-qd (qd-value x)) |
|---|
| 793 | (make-instance 'qd-complex |
|---|
| 794 | :real c |
|---|
| 795 | :imag s))) |
|---|
| 796 | |
|---|
| 797 | (defmethod phase ((x number)) |
|---|
| 798 | (cl:phase x)) |
|---|
| 799 | |
|---|
| 800 | (defmethod phase ((x qd-real)) |
|---|
| 801 | (if (minusp x) |
|---|
| 802 | (- +pi+) |
|---|
| 803 | (make-instance 'qd-real :value (make-qd-d 0d0)))) |
|---|
| 804 | |
|---|
| 805 | (defun signum (number) |
|---|
| 806 | "If NUMBER is zero, return NUMBER, else return (/ NUMBER (ABS NUMBER))." |
|---|
| 807 | (if (zerop number) |
|---|
| 808 | number |
|---|
| 809 | (if (rationalp number) |
|---|
| 810 | (if (plusp number) 1 -1) |
|---|
| 811 | (/ number (abs number))))) |
|---|
| 812 | |
|---|
| 813 | (defmethod random ((x cl:real) &optional (state *random-state*)) |
|---|
| 814 | (cl:random x state)) |
|---|
| 815 | |
|---|
| 816 | (defmethod random ((x qd-real) &optional (state *random-state*)) |
|---|
| 817 | (* x (make-instance 'qd-real |
|---|
| 818 | :value (octi:random-qd state)))) |
|---|
| 819 | |
|---|
| 820 | (defmethod float-digits ((x cl:real)) |
|---|
| 821 | (cl:float-digits x)) |
|---|
| 822 | |
|---|
| 823 | (defmethod float-digits ((x qd-real)) |
|---|
| 824 | (* 4 (float-digits 1d0))) |
|---|
| 825 | |
|---|
| 826 | (defmethod rational ((x real)) |
|---|
| 827 | (cl:rational x)) |
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| 828 | |
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| 829 | (defmethod rational ((x qd-real)) |
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| 830 | (with-qd-parts (x0 x1 x2 x3) |
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| 831 | (qd-value x) |
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| 832 | (+ (cl:rational x0) |
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| 833 | (cl:rational x1) |
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| 834 | (cl:rational x2) |
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| 835 | (cl:rational x3)))) |
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| 836 | |
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| 837 | (defmethod rationalize ((x cl:real)) |
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| 838 | (cl:rationalize x)) |
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| 839 | |
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| 840 | ;;; The algorithm here is the method described in CLISP. Bruno Haible has |
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| 841 | ;;; graciously given permission to use this algorithm. He says, "You can use |
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| 842 | ;;; it, if you present the following explanation of the algorithm." |
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| 843 | ;;; |
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| 844 | ;;; Algorithm (recursively presented): |
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| 845 | ;;; If x is a rational number, return x. |
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| 846 | ;;; If x = 0.0, return 0. |
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| 847 | ;;; If x < 0.0, return (- (rationalize (- x))). |
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| 848 | ;;; If x > 0.0: |
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| 849 | ;;; Call (integer-decode-float x). It returns a m,e,s=1 (mantissa, |
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| 850 | ;;; exponent, sign). |
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| 851 | ;;; If m = 0 or e >= 0: return x = m*2^e. |
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| 852 | ;;; Search a rational number between a = (m-1/2)*2^e and b = (m+1/2)*2^e |
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| 853 | ;;; with smallest possible numerator and denominator. |
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| 854 | ;;; Note 1: If m is a power of 2, we ought to take a = (m-1/4)*2^e. |
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| 855 | ;;; But in this case the result will be x itself anyway, regardless of |
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| 856 | ;;; the choice of a. Therefore we can simply ignore this case. |
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| 857 | ;;; Note 2: At first, we need to consider the closed interval [a,b]. |
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| 858 | ;;; but since a and b have the denominator 2^(|e|+1) whereas x itself |
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| 859 | ;;; has a denominator <= 2^|e|, we can restrict the seach to the open |
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| 860 | ;;; interval (a,b). |
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| 861 | ;;; So, for given a and b (0 < a < b) we are searching a rational number |
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| 862 | ;;; y with a <= y <= b. |
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| 863 | ;;; Recursive algorithm fraction_between(a,b): |
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| 864 | ;;; c := (ceiling a) |
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| 865 | ;;; if c < b |
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| 866 | ;;; then return c ; because a <= c < b, c integer |
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| 867 | ;;; else |
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| 868 | ;;; ; a is not integer (otherwise we would have had c = a < b) |
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| 869 | ;;; k := c-1 ; k = floor(a), k < a < b <= k+1 |
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| 870 | ;;; return y = k + 1/fraction_between(1/(b-k), 1/(a-k)) |
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| 871 | ;;; ; note 1 <= 1/(b-k) < 1/(a-k) |
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| 872 | ;;; |
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| 873 | ;;; You can see that we are actually computing a continued fraction expansion. |
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| 874 | ;;; |
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| 875 | ;;; Algorithm (iterative): |
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| 876 | ;;; If x is rational, return x. |
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| 877 | ;;; Call (integer-decode-float x). It returns a m,e,s (mantissa, |
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| 878 | ;;; exponent, sign). |
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| 879 | ;;; If m = 0 or e >= 0, return m*2^e*s. (This includes the case x = 0.0.) |
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| 880 | ;;; Create rational numbers a := (2*m-1)*2^(e-1) and b := (2*m+1)*2^(e-1) |
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| 881 | ;;; (positive and already in lowest terms because the denominator is a |
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| 882 | ;;; power of two and the numerator is odd). |
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| 883 | ;;; Start a continued fraction expansion |
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| 884 | ;;; p[-1] := 0, p[0] := 1, q[-1] := 1, q[0] := 0, i := 0. |
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| 885 | ;;; Loop |
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| 886 | ;;; c := (ceiling a) |
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| 887 | ;;; if c >= b |
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| 888 | ;;; then k := c-1, partial_quotient(k), (a,b) := (1/(b-k),1/(a-k)), |
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| 889 | ;;; goto Loop |
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| 890 | ;;; finally partial_quotient(c). |
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| 891 | ;;; Here partial_quotient(c) denotes the iteration |
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| 892 | ;;; i := i+1, p[i] := c*p[i-1]+p[i-2], q[i] := c*q[i-1]+q[i-2]. |
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| 893 | ;;; At the end, return s * (p[i]/q[i]). |
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| 894 | ;;; This rational number is already in lowest terms because |
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| 895 | ;;; p[i]*q[i-1]-p[i-1]*q[i] = (-1)^i. |
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| 896 | ;;; |
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| 897 | (defmethod rationalize ((x qd-real)) |
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| 898 | ;; This is a fairly straigtforward implementation of the iterative |
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| 899 | ;; algorithm above. |
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| 900 | (multiple-value-bind (frac expo sign) |
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| 901 | (integer-decode-float x) |
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| 902 | (cond ((or (zerop frac) (>= expo 0)) |
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| 903 | (if (minusp sign) |
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| 904 | (- (ash frac expo)) |
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| 905 | (ash frac expo))) |
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| 906 | (t |
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| 907 | ;; expo < 0 and (2*m-1) and (2*m+1) are coprime to 2^(1-e), |
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| 908 | ;; so build the fraction up immediately, without having to do |
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| 909 | ;; a gcd. |
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| 910 | (let ((a (/ (- (* 2 frac) 1) (ash 1 (- 1 expo)))) |
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| 911 | (b (/ (+ (* 2 frac) 1) (ash 1 (- 1 expo)))) |
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| 912 | (p0 0) |
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| 913 | (q0 1) |
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| 914 | (p1 1) |
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| 915 | (q1 0)) |
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| 916 | (do ((c (ceiling a) (ceiling a))) |
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| 917 | ((< c b) |
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| 918 | (let ((top (+ (* c p1) p0)) |
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| 919 | (bot (+ (* c q1) q0))) |
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| 920 | (/ (if (minusp sign) |
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| 921 | (- top) |
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| 922 | top) |
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| 923 | bot))) |
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| 924 | (let* ((k (- c 1)) |
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| 925 | (p2 (+ (* k p1) p0)) |
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| 926 | (q2 (+ (* k q1) q0))) |
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| 927 | (psetf a (/ (- b k)) |
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| 928 | b (/ (- a k))) |
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| 929 | (setf p0 p1 |
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| 930 | q0 q1 |
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| 931 | p1 p2 |
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| 932 | q1 q2)))))))) |
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| 933 | |
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| 934 | (define-compiler-macro + (&whole form &rest args) |
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| 935 | (declare (ignore form)) |
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| 936 | (if (null args) |
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| 937 | 0 |
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| 938 | (do ((args (cdr args) (cdr args)) |
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| 939 | (res (car args) |
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| 940 | `(two-arg-+ ,res ,(car args)))) |
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| 941 | ((null args) res)))) |
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| 942 | |
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| 943 | (define-compiler-macro - (&whole form number &rest more-numbers) |
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| 944 | (declare (ignore form)) |
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| 945 | (if more-numbers |
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| 946 | (do ((nlist more-numbers (cdr nlist)) |
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| 947 | (result number)) |
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| 948 | ((atom nlist) result) |
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| 949 | (declare (list nlist)) |
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| 950 | (setq result `(two-arg-- ,result ,(car nlist)))) |
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| 951 | `(unary-minus ,number))) |
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| 952 | |
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| 953 | (define-compiler-macro * (&whole form &rest args) |
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| 954 | (declare (ignore form)) |
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| 955 | (if (null args) |
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| 956 | 1 |
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| 957 | (do ((args (cdr args) (cdr args)) |
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| 958 | (res (car args) |
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| 959 | `(two-arg-* ,res ,(car args)))) |
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| 960 | ((null args) res)))) |
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| 961 | |
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| 962 | (define-compiler-macro / (number &rest more-numbers) |
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| 963 | (if more-numbers |
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| 964 | (do ((nlist more-numbers (cdr nlist)) |
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| 965 | (result number)) |
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| 966 | ((atom nlist) result) |
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| 967 | (declare (list nlist)) |
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| 968 | (setq result `(two-arg-/ ,result ,(car nlist)))) |
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| 969 | `(unary-divide ,number))) |
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| 970 | |
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| 971 | ;; Compiler macros to convert <, >, <=, and >= into multiple calls of |
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| 972 | ;; the corresponding two-arg-<foo> function. |
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| 973 | (macrolet |
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| 974 | ((frob (op) |
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| 975 | (let ((method (intern (concatenate 'string |
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| 976 | (string '#:two-arg-) |
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| 977 | (symbol-name op))))) |
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| 978 | `(define-compiler-macro ,op (number &rest more-numbers) |
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| 979 | (do* ((n number (car nlist)) |
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| 980 | (nlist more-numbers (cdr nlist)) |
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| 981 | (res nil)) |
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| 982 | ((atom nlist) |
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| 983 | `(and ,@(nreverse res))) |
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| 984 | (push `(,',method ,n ,(car nlist)) res)))))) |
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| 985 | (frob <) |
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| 986 | (frob >) |
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| 987 | (frob <=) |
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| 988 | (frob >=)) |
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| 989 | |
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| 990 | (define-compiler-macro /= (&whole form number &rest more-numbers) |
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| 991 | ;; Convert (/= x y) to (not (two-arg-= x y)). Should we try to |
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| 992 | ;; handle a few more cases? |
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| 993 | (if (cdr more-numbers) |
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| 994 | form |
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| 995 | `(not (two-arg-= ,number ,(car more-numbers))))) |
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| 996 | |
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| 997 | |
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| 998 | ;; Define compiler macro the convert two-arg-foo into the appropriate |
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| 999 | ;; CL function or QD-REAL function so we don't have to do CLOS |
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| 1000 | ;; dispatch. |
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| 1001 | #+(or) |
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| 1002 | (macrolet |
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| 1003 | ((frob (name cl-op qd-op) |
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| 1004 | `(define-compiler-macro ,name (&whole form x y &environment env) |
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| 1005 | (flet ((arg-type (arg) |
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| 1006 | (multiple-value-bind (def-type localp decl) |
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| 1007 | (ext:variable-information arg env) |
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| 1008 | (declare (ignore localp)) |
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| 1009 | (when def-type |
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| 1010 | (cdr (assoc 'type decl)))))) |
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| 1011 | (let ((x-type (arg-type x)) |
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| 1012 | (y-type (arg-type y))) |
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| 1013 | (cond ((and (subtypep x-type 'cl:number) |
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| 1014 | (subtypep y-type 'cl:number)) |
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| 1015 | `(,',cl-op ,x ,y)) |
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| 1016 | ((and (subtypep x-type 'qd-real) |
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| 1017 | (subtypep y-type 'qd-real)) |
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| 1018 | `(make-instance 'qd-real :value (,',qd-op (qd-value ,x) |
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| 1019 | (qd-value ,y)))) |
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| 1020 | (t |
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| 1021 | ;; Don't know how to handle this, so give up. |
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| 1022 | form))))))) |
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| 1023 | (frob two-arg-+ cl:+ add-qd) |
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| 1024 | (frob two-arg-- cl:- sub-qd) |
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| 1025 | (frob two-arg-* cl:* mul-qd) |
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| 1026 | (frob two-arg-/ cl:/ div-qd)) |
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| 1027 | |
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| 1028 | #+(or) |
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| 1029 | (macrolet |
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| 1030 | ((frob (name cl-op qd-op cl-qd-op qd-cl-op) |
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| 1031 | `(define-compiler-macro ,name (&whole form x y &environment env) |
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| 1032 | (flet ((arg-type (arg) |
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| 1033 | (multiple-value-bind (def-type localp decl) |
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| 1034 | (ext:variable-information arg env) |
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| 1035 | (declare (ignore localp)) |
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| 1036 | (when def-type |
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| 1037 | (cdr (assoc 'type decl)))))) |
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| 1038 | (let ((x-type (arg-type x)) |
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| 1039 | (y-type (arg-type y))) |
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| 1040 | (cond ((subtypep x-type 'cl:float) |
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| 1041 | (cond ((subtypep y-type 'cl:number) |
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| 1042 | `(,',cl-op ,x ,y)) |
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| 1043 | ((subtypep y-type 'qd-real) |
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| 1044 | (if ,cl-qd-op |
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| 1045 | `(make-instance 'qd-real :value (,',cl-qd-op (cl:float ,x 1d0) |
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| 1046 | (qd-value ,y))) |
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| 1047 | form)) |
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| 1048 | (t form))) |
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| 1049 | ((subtypep x-type 'qd-real) |
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| 1050 | (cond ((subtypep y-type 'cl:float) |
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| 1051 | (if ,qd-cl-op |
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| 1052 | `(make-instance 'qd-real :value (,',qd-cl-op (qd-value ,x) |
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| 1053 | (float ,y 1d0))) |
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| 1054 | form)) |
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| 1055 | ((subtypep y-type 'qd-real) |
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| 1056 | `(make-instance 'qd-real :value (,',qd-op (qd-value ,x) |
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| 1057 | (qd-value ,y)))) |
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| 1058 | (t form))) |
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| 1059 | (t |
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| 1060 | ;; Don't know how to handle this, so give up. |
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| 1061 | form))))))) |
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| 1062 | (frob two-arg-+ cl:+ add-qd add-d-qd add-qd-d) |
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| 1063 | (frob two-arg-- cl:- sub-qd sub-d-qd sub-qd-d) |
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| 1064 | (frob two-arg-* cl:* mul-qd mul-d-qd mul-qd-d) |
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| 1065 | (frob two-arg-/ cl:/ div-qd nil nil)) |
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| 1066 | |
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| 1067 | |
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| 1068 | (defun read-qd-real-or-complex (stream) |
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| 1069 | (let ((c (peek-char t stream))) |
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| 1070 | (cond ((char= c #\() |
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| 1071 | ;; Read a QD complex |
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| 1072 | (read-char stream) ; Skip the paren |
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| 1073 | (let ((real (read stream t nil t)) |
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| 1074 | (imag (read stream t nil t))) |
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| 1075 | (unless (char= (peek-char t stream) #\)) |
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| 1076 | (error "Illegal QD-COMPLEX number format")) |
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| 1077 | ;; Read closing paren |
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| 1078 | (read-char stream) |
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| 1079 | (make-instance 'qd-complex |
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| 1080 | :real (qd-value (float real +qd-real-one+)) |
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| 1081 | :imag (qd-value (float imag +qd-real-one+))))) |
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| 1082 | (t |
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| 1083 | (make-instance 'qd-real :value (read-qd stream)))))) |
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| 1084 | |
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| 1085 | (defun qd-class-reader (stream subchar arg) |
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| 1086 | (declare (ignore subchar)) |
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| 1087 | (when arg |
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| 1088 | (warn "Numeric argument ignored in #~DQ" arg)) |
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| 1089 | (read-qd-real-or-complex stream)) |
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| 1090 | |
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| 1091 | ;; Yow! We redefine the #q reader that is in qd-io.lisp to read in |
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| 1092 | ;; and make a real qd-real float, instead of the hackish |
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| 1093 | ;; %qd-real. |
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| 1094 | (set-dispatch-macro-character #\# #\Q #'qd-class-reader) |
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| 1095 | |
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| 1096 | |
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| 1097 | (defmethod epsilon ((m cl:float)) |
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| 1098 | (etypecase m |
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| 1099 | (single-float single-float-epsilon) |
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| 1100 | (double-float double-float-epsilon))) |
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| 1101 | |
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| 1102 | (defmethod epsilon ((m cl:complex)) |
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| 1103 | (epsilon (realpart m))) |
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| 1104 | |
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| 1105 | (defmethod epsilon ((m qd-real)) |
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| 1106 | ;; What is the epsilon value for a quad-double? This is complicated |
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| 1107 | ;; by the fact that things like (+ #q1 #q1q-100) is representable as |
|---|
| 1108 | ;; a quad-double. For most purposes we want epsilon to be close to |
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| 1109 | ;; the 212 bits of precision (4*53 bits) that we normally have with |
|---|
| 1110 | ;; a quad-double. |
|---|
| 1111 | (scale-float (make-qd-d 1d0) -212)) |
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| 1112 | |
|---|
| 1113 | (defmethod epsilon ((m qd-complex)) |
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| 1114 | (epsilon (realpart m))) |
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