LSL Wiki : llAsin

float llAsin(float val)

Returns the arcsine in radians of val.

Basically, it is the inverse of sine (llSin), just as as division is the inverse of multiplication.

Example:

float sine_return;
float arcsine_return;

sine_return = llSin( 1 );
arcsine_return = llAsin( sine_return );

llOwnerSay( "sine_return = llSin( 1 ) == " + (string)sine_return );
llOwnerSay( "arcsine_return = llAsin( sine_return ) == " + (string)arcsine_return );

This would result in the following messages:

sine_return = llSin( 1 ) == 0.841471
arcsine_return = llAsin( sine_return ) == 1.000000

Compare with llSin.

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Functions | Math