asin

Date:

10-12-2011

NAME

ASIN, DASIN, ASIND, DASIND - Compute arcsine (inverse sine)

SYNOPSIS

ASIN ([X=]x)
DASIN ([X=]x)
ASIND ([X=]x) (Deferred implementation)
DASIND ([X=]x) (Deferred implementation)

STANDARDS

Fortran

Fortran extensions: ASIND and DASIND

DESCRIPTION

ASIN and DASIN return the arcsine in radians. ASIND and DASIND return the arcsine in degrees.

ASIN and ASIND are generic function names; the others are specifics. These are elemental intrinsic functions that accept the following argument:

x

Must be type real. The type and kind type of x is identical to the type and kind type of the return value. The absolute value of x must be <= 1. See the RETURN VALUES section for information on input data types and return values.

These functions evaluate y = arcsin(x).

NOTES

The ASIN and DASIN intrinsic function names can be passed as arguments; the others cannot.

If |x| > 1.0 or x = NaN, ASIN(x) yields NaN.

Note: The asin() function has a Linux-equivalent name. Use the man -aname option to show all manual pages matching name within the MANPATH search path. Manual pages are displayed in the order found.

RETURN VALUES

For ASIN and DASIN, the result is in radians and is in the range -pi/2 <= result <= pi/2. For ASIND and DASIND, the result is in degrees and is in the range -90 <= result <= 90.

ASIN and ASIND return the real arcsine of their real arguments.

DASIN and DASIND return the double-precision arcsine of their double-precision arguments.