ch_math_utils.c File Reference

Functions for performing fixed point arithmetic. https://github.com/dmoulding/log2fix https://github.com/chmike/fpsqrt. More...

#include <invn/soniclib/details/ch_math_utils.h>

Functions
fixed_t	FP_log (fixed_t x)
	Find the natural logarithm in UQ16.16 fixed-point format. More...
fixed_t	FP_log2 (fixed_t x)
	Find the base 2 logarithm in UQ16.16 fixed-point format. More...
fixed_t	FP_sqrt (fixed_t x)
int32_t	sqrt_int32 (int32_t v)
	Compute the square root of a 32-bit integer. More...

Detailed Description

Functions for performing fixed point arithmetic. https://github.com/dmoulding/log2fix https://github.com/chmike/fpsqrt.

Date

July 20, 2017

Author

nparikh

Copyright

Copyright 2017-2021 Chirp Microsystems. All rights reserved.

Integer square root function: Algorithm and code Author Christophe Meessen 1993.

Function Documentation

FP_log()

fixed_t FP_log

(

fixed_t

x

)

Find the natural logarithm in UQ16.16 fixed-point format.

Parameters

x	Find the natural log of the provided number. This number is is UQ16.16 fixed-point format.

Returns

The natural log of x in UQ16.16 format.

This function is adapted from work by dmoulding with very minor changes. The source for the original function, logfix, can be found here:

https://github.com/dmoulding/log2fix/blob/master/log2fix.c

FP_log2()

fixed_t FP_log2

(

fixed_t

x

)

Find the base 2 logarithm in UQ16.16 fixed-point format.

Parameters

x	Find the log base-2 of the provided number. This number is is UQ16.16 fixed-point format.

Returns

The log base-2 of x in UQ16.16 format.

This function is adapted from work by dmoulding with very minor changes. The source for the original function, log2fix, can be found here:

https://github.com/dmoulding/log2fix/blob/master/log2fix.c

sqrt_int32()

int32_t sqrt_int32

(

int32_t

v

)

Compute the square root of a 32-bit integer.

Parameters

x	Find the square root of the provided integer.

Returns

The square root of x as a 32-bit integer.

This function is adapted from work by chmike with very minor changes. The source for the original function, sqrt_i32, can be found here:

https://github.com/chmike/fpsqrt/blob/master/fpsqrt.c