Warning: main(/www/www/htdocs/style/globals.php) [function.main]: failed to open stream: No such file or directory in /www/www/docs/6.4.1/neutrino/lib_ref/e/exp.html on line 1
Warning: main() [function.include]: Failed opening '/www/www/htdocs/style/globals.php' for inclusion (include_path='.:/www/www/common:/www/www/php/lib/php') in /www/www/docs/6.4.1/neutrino/lib_ref/e/exp.html on line 1
Warning: main(/www/www/htdocs/style/header.php) [function.main]: failed to open stream: No such file or directory in /www/www/docs/6.4.1/neutrino/lib_ref/e/exp.html on line 8
Warning: main() [function.include]: Failed opening '/www/www/htdocs/style/header.php' for inclusion (include_path='.:/www/www/common:/www/www/php/lib/php') in /www/www/docs/6.4.1/neutrino/lib_ref/e/exp.html on line 8
Compute the exponential function of a number
#include <math.h>
double exp( double x );
float expf( float x );
- x
- The number for which you want to calculate the exponential.
libm
Use the -l m option to
qcc
to link against this library.
The exp() function computes the exponential function of
x
(ex).
A range error occurs if the magnitude of x
is too large.
The exponential value of x.
|
If an error occurs, these functions return 0, but this is also a valid
mathematical result.
If you want to check for errors, set
errno
to 0, call the function, and then check errno again.
These functions don't change errno if no errors occurred. |
#include <stdio.h>
#include <math.h>
#include <stdlib.h>
int main( void )
{
printf( "%f\n", exp(.5) );
return EXIT_SUCCESS;
}
produces the output:
1.648721
ANSI,
POSIX 1003.1
Safety: | |
Cancellation point |
No |
Interrupt handler |
No |
Signal handler |
No |
Thread |
Yes |
The value of expm1(x) may be more accurate than
exp(x) - 1.0 for small values of x.
errno,
expm1,
log()
Warning: main(/www/www/htdocs/style/footer.php) [function.main]: failed to open stream: No such file or directory in /www/www/docs/6.4.1/neutrino/lib_ref/e/exp.html on line 162
Warning: main() [function.include]: Failed opening '/www/www/htdocs/style/footer.php' for inclusion (include_path='.:/www/www/common:/www/www/php/lib/php') in /www/www/docs/6.4.1/neutrino/lib_ref/e/exp.html on line 162