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ERF 3M "Jul 12, 2006" "SunOS 5.11" "Mathematical Library Functions"
NAME
erf, erff, erfl - error function
SYNOPSIS

```c99 [ flag... ] file... -lm [ library... ]
#include <math.h>

double erf(double x);
```

```float erff(float x);
```

```long double erfl(long double x);
```
DESCRIPTION

These functions compute the error function of their argument x, defined as: 2/sqrt(pi)*intregral from 0 to x of exp(-t*t) dt

RETURN VALUES

Upon successful completion, these functions return the value of the error function.

If x is NaN, a NaN is returned.

If x is \(+-0, \(+-0 is returned.

If x is \(+-Inf, \(+-1 is returned.

If x is subnormal, 2/sqrt(\c \c ) * 2 is returned.

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

 ATTRIBUTE TYPE ATTRIBUTE VALUE Interface Stability Standard MT-Level MT-Safe