Function Descriptions
3.27 Complex Multiply of Two Floating Point Numbers
Description:
This module multiplies two floating point complex values.
Y
re
= W
re
∗ X
re
− W
im
∗ X
im
Y
im
= W
re
∗ X
im
+ W
im
∗ X
re
Header File:
FPU.h
Declaration:
complex_float mpy_SP_CSxCS(complex_float w, complex_float x)
Usage:
y = mpy_SP_CSxCS(w,x);
complex_float w
input 1
complex_float x
input 2
complex_float y
result
The type “complex_float” is defined as
typedef struct{
float32 dat[2];
}complex_float;
Element dat[0] is the real part, dat[1] is the imaginary part.
Alignment Requirements:
None
Example:
#include "FPU.h"
complex_float w,x,y;
main()
{
y = mpy_SP_CSxCS(w,x); // complex multiply
}
Benchmark Information:
Number of Cycles = 19 cycles (including the call and return)
Sep 10, 2012 61