C Standard Library Reference Guide (7) math.h

7. math.h

The math header file defines a number of mathematical functions.

Macro:

Huge_val

Function:

ACOs ();

ASIN ();

Atan ();

Atan2 ();

Ceil ();

cos ();

Cosh ();

exp ();

Fabs ();

Floor ();

Fmod ();

Frexp ();

Ldexp ();

Log ();

LOG10 ();

MODF ();

Pow ();

Sin ();

Sinh ();

sqrt ();

Tan ();

Tanh ();

7.1. Error conditions

All MATH.H functions that produce errors are similar.

The variable errno is set to Edom when the argument passed to the function exceeds the parameter definition field required by the function. The return value of a function depends on the implementation.

When the return value is too large to exceed the value range of double, the function returns the macro value Huge_val and sets the variable errno to Erange to represent the overflow. If the value is too small to be represented as a double, the function returns 0. In this case, whether the errno is set to erange depends on the implementation.

Errno,edom, and erange are defined in the header file errno.h.

Note In all cases where no domain restrictions are defined (that is, by default), the values of the parameters are limited by the maximum and minimum values of the double type.