erf(3M)                      (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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