C/math.h/erf

erf: returns the error function of arg

<source lang="cpp">

//Header file: #include <math.h> //Declaration: float erff(float arg);

              double erf(double arg); 
              long double erfl(long double arg);  
 #include <math.h>
 #include <stdio.h>
 int main(void)
 {
    printf("Value of e to the first: %f.", erf(1.0));

 }
        

/* Value of e to the first: 0.842701.*/

      </source>