Changeset 6ab5226ca3e32b443d87934ec138ff0efc8aaecc
 Timestamp:
 04/11/12 20:32:23 (2 years ago)
 Author:
 Raymond Toy <toy.raymond@…>
 Children:
 9fd2ebcbeed3ecae899f732b15fd279f6fb0f14f
 Parents:
 d795ba718dc53f591c82994811f50250aceec1d7
 gitcommitter:
 Raymond Toy <toy.raymond@…> (04/11/12 20:32:23)
 Message:

First cut at Bessel Y. Not working yet.
 Files:

Legend:
 Unmodified
 Added
 Removed

rd795ba

r6ab522


377  377  (format t " sum = ~S~%" sum)))))) 
378  378  
 379  ;; 
379  380  ;; TODO: 
380  381  ;; o For z <= 1 use the series. 
… 
… 

403  404  (sumab bign v z) 
404  405  (sumbigia bign v z))))))))) 
 406  
 407  ;; Bessel Y 
 408  ;; 
 409  ;; bessel_y(v, z) = 1/(2*%pi*%i)*(exp(%i*v*%pi/2)*I(%i*v,z)  exp(%i*v*%pi/2)*I(%i*z, v)) 
 410  ;; + z/v/%pi*((1cos(v*%pi)/z) + S(N,z,v)*cos(v*%pi)S(N,z,v)) 
 411  ;; 
 412  ;; where 
 413  ;; 
 414  ;; S(N,z,v) = sum(alpha[n](z)*a[n](0,v) + beta[n](z)*sum(exp(k*z)*a[n](k,v),k,1,N),n,0,inf) 
 415  ;; + sum(A[n](v)*I[n](N+1/2,z,v),n,0,inf) 
 416  ;; 
 417  (defun bessely (v z) 
 418  (flet ((ipart (v z) 
 419  (let* ((iz (* #c(0 1) z)) 
 420  (c+ (exp (* v (floatpi z) 1/2))) 
 421  (c (exp (* v (floatpi z) 1/2))) 
 422  (i+ (exparci2 iz v)) 
 423  (i (exparci2 ( iz) v))) 
 424  (/ ( (* c i+) (* c+ i)) 
 425  (* #c(0 2) (floatpi z))))) 
 426  (s (bign z v) 
 427  (+ (sumab bign v z) 
 428  (sumbigia bign v z)))) 
 429  (let* ((bign 100) 
 430  (vpi (* v (floatpi z))) 
 431  (c (cos vpi))) 
 432  (+ (ipart v z) 
 433  (* (/ z vpi) 
 434  (+ (/ ( 1 c) 
 435  z) 
 436  (* c 
 437  (s bign z v)) 
 438  ( (s bign z ( v))))))))) 
 439  
 440  
405  441  
406  442  (defun parisseries (v z n) 