IQmath Library

IQNfrac
Fractional part of IQN number
Description
This function returns the fractional portion of IQ number.
Declaration
Global IQ function (IQ format = GLOBAL_Q)
_iq _IQfrac( _iq A)
Q format specific IQ function (IQ format = IQ1 to IQ30)
iqN _IQNfrac ( _iqN A)
Input
Global IQ function (IQ format = GLOBAL_Q)
Fixed point IQ number in GLOBAL_Q format.
Q format specific IQ function (IQ format = IQ1 to IQ30)
Fixed point IQ number in IQN format.
Output
Fractional part of the IQ number
Usage
Example 1: Extracting Integer & fractional part of IQ number
Following example extracts integer & fractional part of two IQ numbers
_iq Y0 = _IQ(2.3456);
_iq Y1 = _IQ(-2.3456);
long Y0int, Y1int;
_iq Y0frac, Y1frac;
Y0int = _IQint(Y0); // Y0int = 2
Y1int = _IQint(Y1); // Y1int = -2
Y0frac = _IQfrac(Y0); // Y0frac = 0.3456
Y1frac = _IQfrac(Y1); // Y1frac = -0.3456
Example 2: Building IQ number from integer & Fractional part
Following example shows how to rebuild the IQ value from the integer
and fractional portions:
_iq Y;
long Yint;
_iq Yfrac;
Y = _IQmpyI32(_IQ(1.0), Yint) + Yfrac;
©Texas Instruments Inc., June 2002 18