log1pd64(3M)log1pd64(3M)NAMElog1pd64(), log1pd128(), log1pd32() - decimal natural logarithm of one-
plus-argument functions
SYNOPSISDESCRIPTION
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 (((1+x)**n)-1)/x are accurate when x is very small, namely:
The preceding example might be applicable when calculating small daily
interest rates.
is a version of it takes a argument and returns a result.
is a version of it takes a argument and returns a result.
These math functions are supported for HP-UX 11i Version 3 September
2008 Update and forward.
USAGE
To use any of these functions, compile with the option.
Make sure your program defines and then includes
Link in the math library by specifying or on the linking command line.
For more information, see the at the following site:
RETURN VALUE
If x is +infinity, returns +infinity.
If x is -1, returns −infinity and raises the divide-by-zero exception.
If x is less than -1, returns NaN and raises the invalid exception.
If x is NaN, returns NaN.
raises the inexact exception whenever a rounded result does not equal
the mathematical result.
ERRORS
If x is less than -1, sets to
If x is -1, sets to
SEE ALSOannuity(3M), compound(3M), expm1d64(3M), log10d64(3M), log2d64(3M),
logd64(3M), math(5).
STANDARDS CONFORMANCE
These functions conform to ISO/IEC TR 24732, "Extension for the pro‐
gramming language C to support decimal floating-point arithmetic".
HP Integrity Server Only log1pd64(3M)