erfc(3) [osf1 man page]

erf(3)							     Library Functions Manual							    erf(3)

NAME

       erf, erfc - Error functions

LIBRARY

       Math Library (libm.a)

SYNOPSIS

       #include <math.h>

       double  erf    (double  x);  float  erff  (float  x); long double erfl	(long double x); double erfc  (double x); float  erfcf (float  x);
       long double erfcl  (long double x);

STANDARDS

       Interfaces documented on this reference page conform to industry standards as follows:

       erf():  XPG4

       erfc():	XPG4

       Refer to the standards(5) reference page for more information about industry standards and associated tags.

DESCRIPTION

       The erf(), erff(), and erfl() functions return the error function of x, where erf(x), erff(x), and erfl(x)  equal  (2/sqrt(pi))	times  the
       area under the curve e**(-t**2) between 0 and x.

       The  erfc(), erfcf(),  and erfcl() functions return (1.0 - erf(x)).  The erfc() function can result in an underflow as x gets large.  delim
       off

																	    erf(3)

erf(3M) 						  Mathematical Library Functions						   erf(3M)

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(pi) * 2 is returned.

ATTRIBUTES

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

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

SEE ALSO

       erfc(3M), feclearexcept(3M), fetestexcept(3M), isnan(3M), math.h(3HEAD), attributes(5), standards(5)

SunOS 5.11							    12 Jul 2006 							   erf(3M)