Standard C++ Library Reference ISO/IEC (VERSION3)

float ldexpf(float x, int ex); [required with C99]
long double ldexpl(long double x, int ex); [required with C99]
The function returns x * 2^ex.
log, logf, logl
double log(double x);
float log(float x); [C++ only]
long double log(long double x); [C++ only]
float logf(float x); [required with C99]
long double logl(long double x); [required with C99]
The function returns the natural logarithm of x. A domain error occurs if x < 0.
log10, log10f, log10l
double log10(double x);
float log10(float x); [C++ only]
long double log10(long double x); [C++ only]
float log10f(float x); [required with C99]
long double log10l(long double x); [required with C99]
The function returns the base-10 logarithm of x. A domain error occurs if x < 0.
modf, modff, modfl
double modf(double x, double *pint);
float modf(float x, float *pint); [C++ only]
long double modf(long double x,
long double *pint); [C++ only]
float modff(float x, float *pint); [required with C99]
long double modfl(long double x,
long double *pint); [required with C99]
The function determines an integer i plus a fraction frac that represent the value of x. It
returns the value frac and stores the integer i in *pint, such that:
x == frac + i●
|frac| is in the interval [0, 1)●
both frac and i have the same sign as x●