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/*
* Scilab ( http://www.scilab.org/ ) - This file is part of Scilab
* Copyright (C) 2008 - INRIA - Arnaud TORSET
*
* This file must be used under the terms of the CeCILL.
* This source file is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at
* http://www.cecill.info/licences/Licence_CeCILL_V2-en.txt
*
*/
#include "fftshift.h"
static void Pair(float* in,int rows,int columns,float* out){
int i=0,j=0;
for (i=0;i<rows;i++)
for(j=0;j<columns;j++)
out[i+j*rows]=in[i+((j+columns/2)%columns)*rows];
}
static void Odd(float* in,int rows,int columns,float* out){
int i=0,j=0;
/*
same as Pair with some change in the indice
*/
for (i=0;i<rows;i++)
for(j=0;j<columns;j++)
out[i+j*rows]=in[i+((j+(columns+1)/2)%columns)*rows];
}
void scolumnfftshifta(float* in,int rows,int columns,float* out){
switch(columns%2){
case 0 : Pair(in,rows,columns,out); break;
case 1 : Odd(in,rows,columns,out); break;
default : break;
}
}
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