initial commit / add all books

1 files changed, 25 insertions, 0 deletions

diff --git a/125/DEPENDENCIES/fft2d.sce b/125/DEPENDENCIES/fft2d.sce
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+++ b/125/DEPENDENCIES/fft2d.sce
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+function [a2] = fft2d(a) 

+//a = any real or complex 2D matrix

+//a2 = 2D-DFT of 2D matrix  'a'

+m=size(a,1)

+n=size(a,2)

+// fourier transform along the rows

+for i=1:n

+a1(:,i)=exp(-2*%i*%pi*(0:m-1)'.*.(0:m-1)/m)*a(:,i) 

+end

+// fourier transform along the columns

+for j=1:m

+a2temp=exp(-2*%i*%pi*(0:n-1)'.*.(0:n-1)/n)*(a1(j,:)).' 

+a2(j,:)=a2temp.'

+end

+for i = 1:m

+    for j = 1:n

+        if((abs(real(a2(i,j)))<0.0001)&(abs(imag(a2(i,j)))<0.0001))

+            a2(i,j)=0;

+        elseif(abs(real(a2(i,j)))<0.0001)

+            a2(i,j)= 0+%i*imag(a2(i,j));

+        elseif(abs(imag(a2(i,j)))<0.0001)

+            a2(i,j)= real(a2(i,j))+0;

+        end

+    end

+end
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