CXLOG1P 3CW "27 September 2009" "mathcw-1.00"

Table of contents


NAME

cxlog1pf, cxlog1p, cxlog1pl, cxlog1pw, cxlog1pq, cxlog1pll, cxlog1pdf, cxlog1pd, cxlog1pdl, cxlog1pdll - complex natural (base-e) logarithm function of one plus argument with real arithmetic

SYNOPSIS

cc [ flags ] -I/usr/local/include file(s) -L/usr/local/lib -lmcw [ ... ]

#include <mathcw.h>

#include <cxcw.h>

extern void cxlog1pf (cx_float result, cx_float z);

extern void cxlog1p (cx_double result, cx_double z);

extern void cxlog1pl (cx_long_double result, cx_long_double z);

extern void cxlog1pw (cx_float80 result, cx_float80 z);

extern void cxlog1pq (cx_float128 result, cx_float128 z);

extern void cxlog1pll (cx_long_long_double result, cx_long_long_double z);

extern void cxlog1pdf (cx_decimal_float result, cx_decimal_float z);

extern void cxlog1pd (cx_decimal_double result, cx_decimal_double z);

extern void cxlog1pdl (cx_decimal_long_double result, cx_decimal_long_double z);

extern void cxlog1pdll (cx_decimal_long_long_double result, cx_decimal_long_long_double z);

NB: Functions with prototypes containing underscores in type names may be available only with certain extended compilers.


DESCRIPTION

Compute the complex natural logarithm of the complex value 1 + z, where z is a two-element array with the real and imaginary parts in that order, that is, the logarithm to the base e (= 2.718281828...) of 1 + z.

The cx family of functions provide limited support for complex arithmetic when compiler or language support for a complex type is lacking.


BRANCH CUTS

There is a branch cut in surface of the imaginary part of the complex logarithm on the entire negative real axis. There is a branch point in the surface of the real part at the origin.

RETURN VALUES

Return the complex natural logarithm.

ERRORS

For finite complex arguments, the returned value is complex and finite. For infinite arguments, at least one component of the returned value is Infinity. Otherwise, for NaN arguments, at least one component of the returned value is a quiet NaN.

SEE ALSO

atan2(3CW), cxabs(3CW), cxarg(3CW), cxexp(3CW), cxexpm1(3CW), cxlog(3CW), hypot(3CW), log(3CW), log1p(3CW).