Page MenuHomec4science
Files F122474753

mtimes2x2.c
No OneTemporary
Actions

File Metadata

Created
Fri, Jul 18, 01:45

mtimes2x2.c
View Options

#include <math.h>
#include <matrix.h>
#include <mex.h>
void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
{
/*declare variables*/
const mwSize *dims;
mwIndex indx;
int i, numdims;
int numelin;
mxClassID classid;
double *input1r, *input1i, *input2r, *input2i, *output1r, *output1i;
double a, b, c, d, e, f, g, h;
double ai, bi, ci, di, ei, fi, gi, hi;
/*figure out the classid*/
classid = mxGetClassID(prhs[0]);
/*check inputs*/
if (nrhs!=2)
mexErrMsgTxt("Wrong number of input arguments");
/*associate inputs*/
input1r = mxGetData(prhs[0]);
input1i = mxGetImagData(prhs[0]);
input2r = mxGetData(prhs[1]);
input2i = mxGetImagData(prhs[1]);
/*figure out dimension info and number of elements*/
dims = mxGetDimensions(prhs[0]);
numdims = mxGetNumberOfDimensions(prhs[0]);
numelin = mxGetNumberOfElements(prhs[0]);
/*associate output*/
if (input1i == NULL && input2i == NULL)
{
plhs[0] = mxCreateNumericArray(numdims, dims, classid, mxREAL);
output1r = mxGetData(plhs[0]);
}
else
{
plhs[0] = mxCreateNumericArray(numdims, dims, classid, mxCOMPLEX);
output1r = mxGetData(plhs[0]);
output1i = mxGetImagData(plhs[0]);
}
/* do the computation*/
if (input1i == NULL && input2i == NULL)
{
for (i=0; i<numelin/4; i++)
{
a = input1r[i*4 ];
b = input1r[i*4+1];
c = input1r[i*4+2];
d = input1r[i*4+3];
e = input2r[i*4 ];
f = input2r[i*4+1];
g = input2r[i*4+2];
h = input2r[i*4+3];
output1r[i*4 ] = a*e + c*f;
output1r[i*4+1] = b*e + d*f;
output1r[i*4+2] = a*g + c*h;
output1r[i*4+3] = b*g + d*h;
}
return;
}
else if (input1i == NULL)
{
for (i=0; i<numelin/4; i++)
{
/*matrix 1*/
a = input1r[i*4 ]; b = input1r[i*4+1]; c = input1r[i*4+2]; d = input1r[i*4+3];
/*matrix 2*/
e = input2r[i*4 ]; f = input2r[i*4+1]; g = input2r[i*4+2]; h = input2r[i*4+3];
ei = input2i[i*4 ]; fi = input2i[i*4+1]; gi = input2i[i*4+2]; hi = input2i[i*4+3];
/*fill in the real part of the output matrix*/
output1r[i*4 ] = a*e + c*f;
output1r[i*4+1] = b*e + d*f;
output1r[i*4+2] = a*g + c*h;
output1r[i*4+3] = b*g + d*h;
/*fill in the imaginary part of the output matrix*/
output1i[i*4 ] = a*ei + c*fi;
output1i[i*4+1] = b*ei + d*fi;
output1i[i*4+2] = a*gi + c*hi;
output1i[i*4+3] = b*gi + d*hi;
}
return;
}
else if (input2i == NULL)
{
for (i=0; i<numelin/4; i++)
{
/*matrix 1*/
a = input1r[i*4 ]; b = input1r[i*4+1]; c = input1r[i*4+2]; d = input1r[i*4+3];
ai = input1i[i*4 ]; bi = input1i[i*4+1]; ci = input1i[i*4+2]; di = input1i[i*4+3];
/*matrix 2*/
e = input2r[i*4 ]; f = input2r[i*4+1]; g = input2r[i*4+2]; h = input2r[i*4+3];
/*fill in the real part of the output matrix*/
output1r[i*4 ] = a*e + c*f;
output1r[i*4+1] = b*e + d*f;
output1r[i*4+2] = a*g + c*h;
output1r[i*4+3] = b*g + d*h;
/*fill in the imaginary part of the output matrix*/
output1i[i*4 ] = ai*e + ci*f;
output1i[i*4+1] = bi*e + di*f;
output1i[i*4+2] = ai*g + ci*h;
output1i[i*4+3] = bi*g + di*h;
}
return;
}
else
{
for (i=0; i<numelin/4; i++)
{
/*matrix 1*/
a = input1r[i*4 ]; b = input1r[i*4+1]; c = input1r[i*4+2]; d = input1r[i*4+3];
ai = input1i[i*4 ]; bi = input1i[i*4+1]; ci = input1i[i*4+2]; di = input1i[i*4+3];
/*matrix 2*/
e = input2r[i*4 ]; f = input2r[i*4+1]; g = input2r[i*4+2]; h = input2r[i*4+3];
ei = input2i[i*4 ]; fi = input2i[i*4+1]; gi = input2i[i*4+2]; hi = input2i[i*4+3];
/*fill in the real part of the output matrix*/
output1r[i*4 ] = (a*e-ai*ei) + (c*f-ci*fi);
output1r[i*4+1] = (b*e-bi*ei) + (d*f-di*fi);
output1r[i*4+2] = (a*g-ai*gi) + (c*h-ci*hi);
output1r[i*4+3] = (b*g-bi*gi) + (d*h-di*hi);
/*fill in the imaginary part of the output matrix*/
output1i[i*4 ] = (ai*e+a*ei) + (ci*f+c*fi);
output1i[i*4+1] = (bi*e+b*ei) + (di*f+d*fi);
output1i[i*4+2] = (ai*g+a*gi) + (ci*h+c*hi);
output1i[i*4+3] = (bi*g+b*gi) + (di*h+d*hi);
}
return;
}
}

Event Timeline

c4science · Help