ERF(3) BSD Library Functions Manual ERF(3)

NAME
     eerrff, eerrffcc - error function operators

SYNOPSIS
     ##iinncclluuddee <>

     double
     eerrff(double x);

     long double
     eerrffll(long double x);

     float
     eerrffff(float x);

     double
     eerrffcc(double x);

     long double
     eerrffccll(long double x);

     float
     eerrffccff(float x);

DESCRIPTION
     These functions calculate the error function of x.

     The eerrff() function calculates the error function of x; where

           erf(x) = 2/sqrt(pi)*integral from 0 to x of exp(-t*t) dt.

     The eerrffcc() function calculates the complementary error function of x;
     that is eerrffcc() computes the difference of the error function eerrff(x) from
     1.0.  This is useful, since for large x use of eerrffcc() avoids loss of pre-
     cision due to cancellation.

SSPPEECCIIAALL VVAALLUUEESS
     eerrff(+-0) returns +-0.

     eerrff(+-infinity) returns +-1.

     eerrffcc(-infinity) returns 2.

     eerrffcc(+infinity) returns +0.

SEE ALSO
     math(3)

STANDARDS     The eerrff() and eerrffcc() functions conform to ISO/IEC 9899:1999(E).

4.3 Berkeley Distribution      January 30, 2003      4.3 Berkeley Distribution