exp2, exp2f, exp2l

Computes 2 raised to the specified value.

Syntax

double exp2(
   double x
);

float exp2(
   float x
);  // C++ only

long double exp2(
   long double x
); // C++ only

float exp2f(
   float x
);

long double exp2l(
   long double x
);
#define exp2(X) // Requires C11 or higher

Parameters

x
The value of the exponent.

Return value

If successful, returns the base-2 exponent of x, that is, 2^x. Otherwise, it returns one of the following values:

Errors are reported as specified in _matherr.

Remarks

Because C++ allows overloading, you can call overloads of exp2 that take and return float and long double types. In a C program, unless you're using the <tgmath.h> macro to call this function, exp2 always takes and returns a double, unless you use the macro in <tgmath.h>.

If you use the <tgmath.h> exp2() macro, the type of the argument determines which version of the function is selected. See Type-generic math for details.

By default, this function's global state is scoped to the application. To change this behavior, see Global state in the CRT.

Requirements

For more compatibility information, see Compatibility.

See also

Alphabetical function reference
exp, expf, expl log2, log2f, log2l