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exp

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< c‎ | numeric‎ | math
Revision as of 03:55, 23 March 2014 by Newatthis (Talk | contribs)

 
 
 
Common mathematical functions
Functions
Basic operations
(C99)
(C99)
(C99)
(C99)
(C99)
(C99)(C99)(C99)
Exponential functions
exp
(C99)
(C99)
(C99)
(C99)
Power functions
(C99)
(C99)
Trigonometric and hyperbolic functions
(C99)
(C99)
(C99)
Error and gamma functions
(C99)
(C99)
(C99)
(C99)
Nearest integer floating point operations
(C99)(C99)(C99)
(C99)
(C99)(C99)(C99)
Floating point manipulation functions
(C99)(C99)
(C99)
(C99)
Classification
(C99)
(C99)
(C99)
Macro constants
 
Defined in header <math.h>
float       expf( float arg );
(since C99)
double      exp( double arg );
long double expl( long double arg );
(since C99)

Computes the e (Euler's number, 2.7182818) raised to the given power arg

Contents

Parameters

arg - floating point value

Return value

e raised to the power arg

If the result is too large for the underlying type, range error occurs and HUGE_VAL is returned.


Example

#include <stdio.h>
#include <math.h>
#include <errno.h>
 
int main()
{
    printf("exp(1.0)       = %f\n", exp(1.0));
    printf("log(2.718282)  = %f\n", log(2.718282));   /* inverse of exp */
    printf("exp(+0)        = %f\n", exp(+0));
    printf("exp(-0)        = %f\n", exp(-0));
    printf("exp(+INFINITY) = %f\n", exp(+INFINITY));
    printf("exp(-INFINITY) = %f\n", exp(-INFINITY));
    printf("exp(NAN)       = %f\n", exp(NAN));
 
    /* range error */
    errno = 0;
    printf("exp(710.0)     = %f\n", exp(710.0));
    printf("errno          = %d\n", errno);
 
    return 0;
}

Possible output:

exp(1.0)       = 2.718282
log(2.718282)  = 1.000000
exp(+0)        = 1.000000
exp(-0)        = 1.000000
exp(+INFINITY) = inf
exp(-INFINITY) = 0.000000
exp(NAN)       = nan
exp(710.0)     = inf
errno          = 34

See also

(C99)(C99)
computes natural (base-e) logarithm (ln(x))
(function) [edit]
(C99)(C99)
computes a number raised to the given power (xy)
(function) [edit]