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/* Author: Bill Hoff,2-114C,8645,3563478 (hoff) at uicsl */
/*!
* \fn int mult (double *v1[2], int size1, double *v2[2], int size2, double *v3[2], int size3)
*
* \brief Multiply two complex vectors, point by point
*
* Vectors are in the form: real, imaginary (each a floating number).
* A vector can be of any size. Computes <b>v3</b> = <b>v1</b> *
* <b>v2</b>. <b>v3</b> should as big as the biggest of <b>v1</b> and
* <b>v2</b>.
*
* \param v1
* \param size1
* \param v2
* \param size2
* \param v3
* \param size3
* \return int
*/
int
mult(double *v1[2], int size1, double *v2[2], int size2, double *v3[2],
int size3)
{
int i, n;
n = (size1 < size2 ? size1 : size2); /* get the smaller size */
for (i = 0; i < n; i++) {
*(v3[0] + i) =
*(v1[0] + i) * *(v2[0] + i) - *(v1[1] + i) * *(v2[1] + i);
*(v3[1] + i) =
*(v1[0] + i) * *(v2[1] + i) + *(v2[0] + i) * *(v1[1] + i);
}
/* if unequal size, zero out remaining elements of larger vector */
if (size1 != size2)
for (i = n; i < size3; i++) {
*(v3[0] + i) = 0.0;
*(v3[1] + i) = 0.0;
}
return 0;
}
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