tan

Date:

03-15-23

NAME

TAN, DTAN, TAND, DTAND - Compute tangent

SYNOPSIS

TAN ([X=]x)
DTAN ([X=]x)
TAND ([X=]x) (Deferred implementation)
DTAND ([X=]x) (Deferred implementation)

STANDARDS

Fortran

Fortran extensions: TAND, DTAND

DESCRIPTION

These functions evaluate y= tan(x). They are elemental intrinsic functions that accept the following argument:

x

Must be of type real. For TAN and DTAN, x must be specified in radians and is treated as modulo 2 * pi. For TAND and DTAND, x must be specified in degrees and is treated as modulo 360.

TAN and TAND are generic function names; the rest are specifics.

NOTES

The TAN and DTAN intrinsic function names can be passed as arguments; the others cannot.

The following returns occur:

  • TAN(x), TAND(x), DTAN(x),

and DTAND(x) all yield NaN if x is infinite or NaN.

Note: The tan() 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

TAN and TAND return the real tangent of their real argument.

DTAN and DTAND return the double-precision real tangent of their double-precision real argument.