asin()

Return the arcsine of the argument.

Syntax
Parameter
Description
Example

Syntax

asin( sine )

Parameter

Parameter	Definition
sine	sine argument Valid Values -1 ≤ sine ≤ 1

Description

The asin() function returns the arcsine of sine, that is, the length in radians of the arc whose sine is sine. The output range for the asin() function is -p/2 ≤ asin() ≤ p/2.

Example

The following PSL script uses the asin() function to confirm the trigonometric identity Arcsin x + Arccos x = π/2:

PI = 3.141593;
HALFPI = PI / 2;
print("Arcsine + Arccosine Identity Verification\n\n");
print(" Sine Expected Returned\n");
print("--------- --------- ---------\n");
sine = -0.9;
while (sine < 1.0){
printf("%+8.6f %+8.6f %+8.6f\n",sine,HALFPI,asin(sine) + acos(sine));
sine = sine + 0.1;
}