log1p(3M)log1p(3M)NAMElog1p(), log1pf(), log1pl(), log1pw(), log1pq() - natural logarithm of
one-plus-argument functions
SYNOPSIS
HP Integrity Server Only
DESCRIPTION
The function computes the logarithmic function but may be more accurate
for very small values of x.
The and functions are useful to guarantee that financial calculations
of are accurate when x is very small, namely:
The preceding example would be applicable when calculating small daily
interest rates. See also and
Integrity Server Only
is a version of it takes a argument and returns a result.
is a version of it takes a argument and returns a result.
is an version of it takes an argument and returns an result.
is equivalent to on HP-UX systems.
USAGE
To use these functions, compile either with the default option or with
the and options.
To use (for Integrity servers) or compile also with the option.
Make sure your program includes and link in the math library by speci‐
fying on the compiler or linker command line.
For more information, see the at the following site:
RETURN VALUE
If x is +INFINITY, returns +INFINITY.
If x = -1.0, returns (equal to −INFINITY) and raises the divide-by-zero
exception.
If x < -1.0, returns NaN and raises the invalid exception.
If x is NaN, returns NaN.
When it raises no other exception, whether raises the inexact exception
is unspecified.
ERRORS
If x < -1.0, sets to
Integrity Server Only
HP-UX functions on Integrity servers do not set by default. For set‐
ting, compile with the option.
SEE ALSOannuity(3M), compound(3M), expm1(3M), log(3M), math(5).
STANDARDS CONFORMANCE
: XPG4.2, ANSI C, ISO/IEC C99 (including Annex F, ``IEC 60559 floating-
point arithmetic'')
: ISO/IEC C99 (including Annex F, ``IEC 60559 floating-point arith‐
metic'')
log1p(3M)
