HP-UX Reference (11i v1 05/09) - 3 Library Functions A-M (vol 6)

cosd(3M) cosd(3M)

NAME

cosd(), cosdf() - degree-valued cosine functions

SYNOPSIS

#include <math.h>

double cosd(double x);

float cosdf(float x);

DESCRIPTION

The cosd() function is a degree-valued version of

cos(). It returns the cosine of x (x speciﬁed in

degrees).

The

cosd() function may lose accuracy when x is far from zero.

The

cosdf() function is a float version of

cosd(); it takes a float argument and returns a float

result.

The

cosd() and cosdf() functions are not speciﬁed by any standard, but

cosdf() is named in accor-

dance with the conventions speciﬁed in the "Future Library Directions" section of the ANSI C standard.

To use these functions, compile either with the default

-Ae option or with the -Aa

and

-D_HPUX_SOURCE options. Make sure your program includes <

math.h>. Link in the math library by

specifying

-lm on the compiler or linker command line.

RETURN VALUE

If x is NaN or ±INFINITY, cosd() returns NaN.

If the correct value after rounding would be smaller in magnitude than

MINDOUBLE, cosd() returns

zero.

ERRORS

No errors are deﬁned.