abs
Wondering what is the use of 'acos' function?
It is essential in games, animations and drawings to determine the location of two objects relating to each other.
To the point: the angle of two vectors is calculated by
v1X*v2X + v1Y*v2Y
acos(--------------------------)=angle between two vectors.
|v1| * |v2|
|v1| and |v2| are the length of the vectors and calculated using Pithagoras-formula: |v1|=sqrt(v1X*v1X + v1Y*v1Y)
This helped me to calculate and share given space for 'n' amount of objects so that they don't overlap.
Enjoy! :-)
acos
(PHP 4, PHP 5)
acos — Arco coseno
Descripción
float acos
( float
$arg
)
Devuelve el arco coseno de arg en radianes.
acos() es la función complementaria de
cos(), lo que quiere decir que
a==cos(acos(a)) para cada valor de a en el rango de
acos()'.
Parámetros
-
arg -
El argumento a procesar
Valores devueltos
The arc cosine of arg in radians.
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User Contributed Notes
acos - [2 notes]
zoltan dot szentesi at nokia dot com ¶
6 years ago
anthony at interiorgoodsdirect dot com ¶
5 years ago
To calculate an angle from a triangle's sides.
Use the 'law of cosines' :
<?php
// a²+b²-c²
// cosC = --------
// 2ab
function calculateAngle($c,$a,$b)
{
$angleInRadians=acos((pow($a,2) + pow($b,2) - pow($c,2)) / (2 * $a * $b));
return rad2deg($angleInRadians);
}
?>
$a, $b, $c are the triangle sides.
The function returns the angle opposite side c, in degrees.