{{DISPLAYTITLE:_ASIN}} The [[_ASIN]] function returns the angle measured in radians based on an input [[SIN]]e value ranging from -1 to 1. {{PageSyntax}} : {{Parameter|radian_angle!}} = [[_ASIN]]({{Parameter|sine_value!}}) {{PageDescription}} * The {{Parameter|sine_value!}} must be measured >= -1 and <= 1, or else it will generate a return value of '''-1.#IND''', which is basically QB64's way of telling us that the number doesn't exist. * ARCSINE is the inverse function of [[SIN]]e, and turns a [[SIN]]e value back into an angle. * Note: Due to rounding with floating point math, the [[_ASIN]] may not always give a perfect match for the [[SIN]] angle which generated this. You can reduce the number of rounding errors by increasing the precision of your calculations by using [[DOUBLE]] or [[_FLOAT]] precision variables instead of [[SINGLE]]. {{PageAvailability}} * Version 1.000 and up. {{PageExamples}} ''Example:'' Converting a radian angle to its SINe and using that value to find the angle in degrees again using _ASIN: {{CodeStart}} '' '' {{Cl|DEFDBL}} A-Z {{Cl|INPUT}} "Give me an Angle (in Degrees) => "; Angle {{Cl|PRINT}} C = {{Cl|SIN}}({{Cl|_D2R}}(Angle)) '_D2R is the command to convert Degrees to Radians, which is what SIN expects {{Cl|PRINT}} "The SINE of the Angle is: "; C A = {{Cl|_ASIN}}(C) {{Cl|PRINT}} "The ASIN of "; C; " is: "; A {{Cl|PRINT}} "Notice, A is the Angle in Radians. If we convert it to degrees, the value is "; {{Cl|_R2D}}(A) '' '' {{CodeEnd}} {{small|Example by SMcNeill}} {{OutputStart}} Give me an Angle (in Degrees) => ? 60 The SINE of the Angle is: .8660254037844386 The ACOS of .8660254037844386 is: 1.047197551196598 Notice, A is the Angle in Radians. If we convert it to degrees, we discover the value is 60 {{OutputEnd}} {{PageSeeAlso}} * [[_D2G]] {{text|(degree to gradient}}, [[_D2R]] {{text|(degree to radian)}} * [[_G2D]] {{text|(gradient to degree)}}, [[_G2R]] {{text|(gradient to degree}} * [[_R2D]] {{text|(radian to degree)}}, [[_R2G]] {{text|(radian to gradient}} * [[COS]] {{text|(cosine)}}, [[SIN]] {{text|(sine)}}, [[TAN]] {{text|(tangent)}} * [[_ACOS]] {{text|(arc cosine)}}, [[ATN]] {{text|(arc tangent)}} * [[_ACOSH]] {{text|(arc hyperbolic cosine)}}, [[_ASINH]] {{text|(arc hyperbolic sine)}}, [[_ATANH]] {{text|(arc hyperbolic tangent)}} * [[_ATAN2]] {{text|(Compute arc tangent with two parameters)}} * [[_HYPOT]] {{text|(hypotenuse)}} *[[Mathematical Operations]] *[[Mathematical_Operations#Derived_Mathematical_Functions|Derived Mathematical Functions]] {{PageNavigation}}