Module fixed_math::trig

Trigonometric functions for fixed numbers.

Implementation

We use the CORDIC algorithm, following this paper: Efficient Fixed-Point Trigonometry Using CORDIC Functions For PIC16F - Jose Benavides Microchip Technology Inc. (2007) https://ww1.microchip.com/downloads/en/AppNotes/01061A.pdf

Constants

FRAC_180_PI

180 / π used to convert from radians to degrees

FRAC_PI_180

π / 180 used to convert from degrees to radians

Functions

cos

Compute cos of an angle in degrees.

deg_to_rad

Simply convert a fixed number from degrees to radians by multiplication.

rad_to_deg

Simply convert a fixed number from radians to degrees by multiplication.

sin

Compute sin of an angle in degrees.

sin_cos

Compute sin and cos simultaneously of an angle in degrees.

sin_cos_deg_unchecked

Only works with values in -90 to 90 degrees.

sin_cos_i7

Compute sin and cos simultaneously of an angle in degrees.

sin_cos_i8

Compute sin and cos simultaneously of an angle in degrees.

sin_cos_i9

Compute sin and cos simultaneously of an angle in degrees.

sin_cos_rad

Currently it is very imprecise. You probably want to convert to degrees and use sin_cos instead.

sin_cos_rad_unchecked

Only works for values in -π/2 to π/2 radians

tan

Calculate tangent of an angle in degrees. Returns None when the cos is 0 or on overflow.