ERF(3M)                                                   ERF(3M)



     NAME
          erf, erfc - error function and complementary error function

     SYNOPSIS
          #include <math.h>

          double erf (x)
          double x;

          double erfc (x)
          double x;

     DESCRIPTION                                             x
                                                          _2_∫e-t2dt.
          erf returns the error function of x, defined as   _0
                                                          \/π

          erfc, which returns 1.0 - erf(x), is provided because of the

          extreme loss of relative accuracy if erf(x) is called for

          large x and the result subtracted from 1.0 (e.g., for x = 5,

          12 places are lost).


     SEE ALSO

          exp(3M).


     ORIGIN

          AT&T V.3






























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