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#include <math.h> double log1p(double x); |
This function computes the natural logarithm of 1 + x. It is more accurate than `log(1 + x)' for small values of x.
The natural logarithm of 1 + x. If x is -1, a
negative infinity is returned and errno is set to ERANGE.
If x is less than -1 or +Inf or a NaN, the return
value is NaN and errno is set to EDOM.
| ANSI/ISO C | No |
| POSIX | No |