erf(3M)                  UNIX System V(Math Libraries)                  erf(3M)


NAME
      erf, erfc - error function and complementary error function

SYNOPSIS
      cc [flag ...] file ...  -lm [library ...]

      #include <math.h>

      double erf (double x);

      double erfc (double x);

DESCRIPTION
      erf returns the error function of x, defined as
               x
            _2∫e-t2dt
            \|π0
      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).































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