Functions and CALL Routines 
Returns the probability from a t distribution.

x

is a numeric random variable.

df

is a numeric degrees of freedom parameter.

nc

is an optional numeric noncentrality parameter.
The PROBT function returns the probability
that an observation from a Student's t distribution, with degrees
of freedom df and noncentrality parameter nc, is
less than or equal to x. This function accepts a noninteger degree
of freedom parameter df. If the optional parameter, nc, is not specified or has the value 0, the value that is returned is
from the central Student's t distribution.
The significance level of a twotailed t
test is given by
p=(1probt(abs(x),df))*2;
SAS Statements 
Results 
x=probt(0.9,5);

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