Guardian Native C Library Calls Reference Manual (G06.29+, H06.08+, J06.03+)

catan(3) Guardian Native C Library Calls Reference Manual

NAME

catan - Computes the complex arc tangent

LIBRARY

H-series and J-series native Guardian processes: $SYSTEM.ZDLLnnn.ZCREDLL

32-bit H-series and J-series OSS processes: /G/system/zdllnnn/zcredll

64-bit H-series and J-series OSS processes: /G/system/zdllnnn/ycredll

SYNOPSIS

#include <complex.h>

double complex catan(

double complex z);

PARAMETERS

z Speciﬁes a double complex value.

DESCRIPTION

The catan() function computes the complex arc tangent of z, with branch cuts outside the inter-

val [-i, +i] along the imaginary axis.

NOTES

This function is implemented only for the IEEE_ﬂoat ﬂoating-point option. Applications using

this function cannot be compiled if the speciﬁed ﬂoating-point option is Tandem_ﬂoat.

RETURN VALUES

The catan() function returns the complex arc tangent of z in the range of a strip mathematically

unbound along the imaginary axis and in the interval [-π/2, +π/2] along the real axis.

ERRORS

No errors are deﬁned.

RELATED INFORMATION

Functions: atan(3), catanf(3), catanl(3), ctan(3).

STANDARDS CONFORMANCE

This function conforms to the ISO/IEC 9899:1999 standard.

This function conforms to the IEEE Std 1003.1, 2004 Edition.

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