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exp, expf

Calculates the exponential.

double exp( 
   double x
);
float exp(
   float x
);  // C++ only
long double exp(
   long double x
);  // C++ only
float expf( 
   float x
);

Parameters

  • x
    Floating-point value.

Return Value

The exp function returns the exponential value of the floating-point parameter, x, if successful. That is, the result is e to the power x, where e is the base of the natural logarithm. On overflow, the function returns INF (infinite) and on underflow, exp returns 0.

Input

SEH Exception

Matherr Exception

± QNAN,IND

None

_DOMAIN

± ∞

INVALID

_DOMAIN

x ≥ 7.097827e+002

INEXACT+OVERFLOW

OVERFLOW

X ≤ -7.083964e+002

INEXACT+UNDERFLOW

UNDERFLOW

exp has an implementation that uses Streaming SIMD Extensions 2 (SSE2). See _set_SSE2_enable for information and restrictions on using the SSE2 implementation.

Remarks

C++ allows overloading, so you can call overloads of exp. In a C program, exp always takes and returns a double.

Requirements

Function

Required header

exp, expf

<math.h>

For additional compatibility information, see Compatibility in the Introduction.

Example

// crt_exp.c

#include <math.h>
#include <stdio.h>

int main( void )
{
   double x = 2.302585093, y;

   y = exp( x );
   printf( "exp( %f ) = %f\n", x, y );
}
exp( 2.302585 ) = 10.000000

.NET Framework Equivalent

System::Math::Exp

See Also

Reference

Floating-Point Support

log, logf, log10, log10f

_CIexp