Datatype Conversions

Support for converting floating-point numbers to fixed-point and fixed-point numbers to floating-point. More...

Overview

Support for converting floating-point numbers to fixed-point and fixed-point numbers to floating-point.

These intrinsics can generate exceptions, for more information you can go here.

Note

These intrinsics do real conversions. No bit reinterpretation takes place.

Functions
float	fix2float (int n)
	Fixed-point to Floating-point conversion without scaling.
float	fix2float (int n, int sft)
	Fixed-point to Floating-point conversion with scaling.
int	float2fix (float n)
	Floating-point to Fixed-point conversion without scaling.
int	float2fix (float n, int sft)
	Floating-point to Fixed-point conversion with scaling.

Function Documentation

fix2float() [1/2]

float fix2float

(

int

n

)

Fixed-point to Floating-point conversion without scaling.

Parameters

n	Integer input value

fix2float() [2/2]

float fix2float	(	int	n,
		int	sft
	)

Fixed-point to Floating-point conversion with scaling.

Parameters

n	Integer input value
sft	Binary point of input value. Range [-32:31].

Example:

If the input value has 8 fractional bits, then 0.5 in fixed point will be expressed as 128. To convert this value to float use the following code, which stores 0.5 in floating-point variable b:

int   n = 128;
float b = fix2float(n,8);

float2fix() [1/2]

int float2fix

(

float

n

)

Floating-point to Fixed-point conversion without scaling.

Parameters

n	Floating point input value

float2fix() [2/2]

int float2fix	(	float	n,
		int	sft
	)

Floating-point to Fixed-point conversion with scaling.

Parameters

n	Floating point input value
sft	Binary point of output value. Range [-32:31].

Returns

round(n * pow(2.0, sft)); // round to nearest integer

Example:

The input value is 0.5 and the output shall be of format Q24.8 (meaning 8 fractional bits out of 128 bit integer output word). To convert this value to float use the following code, which stores 128 in fixed-point variable a:

float   n = 0.5;
int a = float2fix(n,8);

Note

To achieve better performance, consider using float2fix(v8float v, int sft) instead