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.TH al_fixtan 3 "" "Allegro reference manual"
.SH NAME
.PP
al_fixtan \- Allegro 5 API
.SH SYNOPSIS
.IP
.nf
\f[C]
#include\ <allegro5/allegro.h>
al_fixed\ al_fixtan(al_fixed\ x);
\f[]
.fi
.SH DESCRIPTION
.PP
This function finds the tangent of a value using a lookup table.
The input value must be a fixed point binary angle.
.PP
Example:
.IP
.nf
\f[C]
\ \ \ \ al_fixed\ angle,\ res_a,\ res_b;
\ \ \ \ float\ dif;
\ \ \ \ angle\ =\ al_itofix(37);
\ \ \ \ /*\ Prove\ that\ tan(angle)\ ==\ sin(angle)\ /\ cos(angle).\ */
\ \ \ \ res_a\ =\ al_fixdiv(al_fixsin(angle),\ al_fixcos(angle));
\ \ \ \ res_b\ =\ al_fixtan(angle);
\ \ \ \ dif\ =\ al_fixtof(al_fixsub(res_a,\ res_b));
\ \ \ \ printf("Precision\ error:\ %f\\n",\ dif);
\f[]
.fi
.SH RETURN VALUE
.PP
Returns the tangent of a fixed point binary format angle.
The return value will be in radians.
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