  # Manual Pages  — ERF

### NAME

erf, erff, erfl, erfc, erfcf, erfcl – error function operators

### LIBRARY

Math Library (libm, -lm)

### SYNOPSIS

`#include <math.h>`

double
erf(double x);

float
erff(float x);

long double
erfl(long double x);

double
erfc(double x);

float
erfcf(float x);

long double
erfcl(long double x);

### DESCRIPTION

These functions calculate the error function of x.

The erf(), erff(), and erfl() functions calculate the error function of x; where erf(x) = 2/sqrt(pi)*integral from 0 to x of exp(-t*t) dt. erf(x) := (2/√π)∫0xexp(-t2)dt.

The erfc(), erfcf(), and erfcl() functions calculate the complementary error function of x; that is erfc() subtracts the result of the error function erf(x) from 1.0.

### HISTORY

The erf() and erfc() functions appeared in BSD 4.3 .

 ERF (3) July 13, 2014 Please direct any comments about this manual page service to Ben Bullock. Privacy policy.

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