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

asin, asinf, asinl
double asin(double x);
float asin(float x); [C++ only]
long double asin(long double x); [C++ only]
float asinf(float x); [required with C99]
long double asinl(long double x); [required with C99]
The function returns the angle whose sine is x, in the range [-pi/2, +pi/2] radians. A domain error
occurs if 1 < |x|.
atan, atanf, atanl
double atan(double x);
float atan(float x); [C++ only]
long double atan(long double x); [C++ only]
float atanf(float x); [required with C99]
long double atanl(long double x); [required with C99]
The function returns the angle whose tangent is x, in the range [-pi/2, +pi/2] radians.
atan2, atan2f, atan2l
double atan2(double y, double x);
float atan2(float y, float x); [C++ only]
long double atan2(long double y, long double x); [C++ only]
float atan2f(float y, float x); [required with C99]
long double atan2l(long double y,
long double x); [required with C99]
The function returns the angle whose tangent is y/x, in the full angular range [-pi, +pi] radians.
A domain error may occur if both x and y are zero.
ceil, ceilf, ceill
double ceil(double x);
float ceil(float x); [C++ only]
long double ceil(long double x); [C++ only]
float ceilf(float x); [required with C99]
long double ceill(long double x); [required with C99]
The function returns the smallest integer value not less than x.