HP C/iX Library Reference Manual (30026-90004)

136 Chapter5
HP C/iX Library Function Descriptions
erf
erf
Returns the statistical error function of the input value.
Syntax
#include <math.h>
double erf (double x );
Parameters
x A real number defining the upper limit of the integral.
Return Values
n The integral given by the error function from 0 to x .
Description
The erf function returns the error function of x , defined as:
Figure 5-1. erf function
See Also
exp(), erfc()
2
π
x
o
e
-t
2
dt