asin(), asinf() arc sine function	Function
	SYNOPSIS DESCRIPTION PARAMETERS RETURN VALUES CONFORMANCE MULTITHREAD SAFETY LEVEL PORTING ISSUES AVAILABILITY SEE ALSO

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SYNOPSIS

#include <math.h>

double asin(double x)

float asinf(float x)

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DESCRIPTION

The asin() and asinf() functions compute the principal value of the arc sine of x in the range [-1, +1].

To check for error situations, set errno to 0 before calling asin(). If errno is non-zero on return, or the return value is NaN, an error has occurred.

The asinf() function is a single-precision version of asin().

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PARAMETERS

x 

A value between -1.0 and 1.0.

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RETURN VALUES

If |x|>1, asin(x) and asinf(x) return the following values based on the math mode being used:

• In IEEE mode, a value of NaN is returned.

• In POSIX mode, a value of 0.0 is returned and the global variable errno is set to EDOM.

• In SVID and XOPEN modes, the matherr() function is called.

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CONFORMANCE

asin(): ANSI/ISO 9899-1990

asinf(): PTC MKS Toolkit UNIX APIs extension

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MULTITHREAD SAFETY LEVEL

MT-Safe.

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PORTING ISSUES

None.

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AVAILABILITY

PTC MKS Toolkit for Professional Developers
PTC MKS Toolkit for Professional Developers 64-Bit Edition
PTC MKS Toolkit for Enterprise Developers
PTC MKS Toolkit for Enterprise Developers 64-Bit Edition

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SEE ALSO

Functions:

acos(), atan(), atan2(), cos(), cosh(), math(), matherr(), sin(), sinh(), tan(), tanh()

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PTC MKS Toolkit 10.4 Documentation Build 39.