SAS 9.1 Language Reference Dictionary, Volumes 1, 2 and 3

Returns the value of the (normal) error function

Category: Mathematical

Syntax

ERF ( argument )

Arguments

argument

Details

The ERF function returns the integral, given by

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Examples

You can use the ERF function to find the probability (p) that a normally distributed random variable with mean 0 and standard deviation will take on a value less than X. For example, the quantity that is given by the following statement is equivalent to PROBNORM(X):

p=.5+.5*erf(x/sqrt(2));

SAS Statements

Results

y=erf(1.0);

0.8427007929

y=erf(-1.0);

-0.842700793

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