Format
#include <math.h> double erf(double x); double erfc(double x);
Language Level: ILE C Extension
Threadsafe: Yes.
Description
The erf() function calculates the error function of:
The erfc() function computes the value of 1.0 - erf(x). The erfc() function is used in place of erf() for large values of x.
Return Value
The erf() function returns a double value that represents the error function. The erfc() function returns a double value representing 1.0 - erf.
Example that uses erf()
This example uses erf() and erfc() to compute the error function of two numbers.
#include <stdio.h> #include <math.h> double smallx, largex, value; int main(void) { smallx = 0.1; largex = 10.0; value = erf(smallx); /* value = 0.112463 */ printf("Error value for 0.1: %lf\n", value); value = erfc(largex); /* value = 2.088488e-45 */ printf("Error value for 10.0: %le\n", value); } /***************** Output should be similar to: ***************** Error value for 0.1: 0.112463 Error value for 10.0: 2.088488e-45 */
Related Information
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