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Dataplot Vol 2 Vol 1

PNRPDF

Name:
    PNRPDF (LET)
Type:
    Library Function
Purpose:
    Compute the standard power-normal probability density function.
Description:
    The standard power-normal distribution has the following probability density function:

      f(x,p)=p*NORPDF(x)*NORCDF(-x)**(p-1)   for p > 0

    where p is the power parameter, and NORCDF and NORPDF are the cumulative distribution function and the probability density function for the standard normal distribution respectively.

    If p is 1, this distribution reduces to the normal distribution.

Syntax:
    LET <y2> = PNRPDF(<y1>,<p>)        <SUBSET/EXCEPT/FOR qualification>
    where <y1> is a number, parameter, or variable;
                  <p> is a positive number, parameter, or variable that specifies the power parameter;
                  <y2> is a variable or a parameter (depending on what <y1> is) where the computed power-normal pdf value is stored;
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
    LET A = PNRPDF(3,2)
    LET X2 = PNRPDF(X1,POW)
    LET X2 = PNRPDF(X1,0.5)
Note:
    The general power-normal distribution has the following probability density function:

      f(x,p,mu,sigma)=(p/sigma)*NORPDF((x-mu)/sigma)*
NORCDF(-(x-mu)/sigma)**(p-1)   for s > 0, p > 0

    where mu and sigma are the location and scale parameters, respectively.

Default:
    None
Synonyms:
    None
Related Commands:
    PNRCDF = Compute the power-normal cumulative distribution function.
    PNRPPF = Compute the power-normal percent point function.
    PNRHAZ = Compute the power-normal hazard function.
    PNRCHAZ = Compute the power-normal cumulative hazard function.
    PLNCDF = Compute the power-lognormal cumulative distribution function.
    PLNPDF = Compute the power-lognormal probability density function.
    PLNPPF = Compute the power-lognormal percent point function.
    LGNCDF = Compute the lognormal cumulative distribution function.
    LGNPDF = Compute the lognormal probability density function.
    LGNPPF = Compute the lognormal percent point function.
    NORCDF = Compute the normal cumulative distribution function.
    NORPDF = Compute the normal probability density function.
    NORPPF = Compute the normal percent point function.
Reference:
    "A Computer Program POWNOR for Fitting the Power-Normal and -Lognormal Models to Life or Strength Data from Specimens of Various Sizes", Nelson and Doganaksoy, NIST-IR 4760, March 1992.
Applications:
    Reliability
Implementation Date:
    1995/5
Program:
    LABEL CASE ASIS
    X1LABEL X
    YLIMITS 0 1.5
    Y1LABEL Probability
    MAJOR YTIC MARK NUMBER 6 
    TITLE CASE ASIS
    TITLE Power Normal PDF Plot CR() ...
     SD=1, P=10000, 3000, 1000, 300, 100, 50, 20, 5, 1, 0.5, 0.2 0.1 
    . 
    PLOT PNRPDF(X,10000) FOR X = -5 .05 5 AND 
    PLOT PNRPDF(X,3000) FOR X = -5 .05 5 AND 
    PLOT PNRPDF(X,1000) FOR X = -5 .05 5 AND 
    PLOT PNRPDF(X,300) FOR X = -5 .05 5 AND 
    PLOT PNRPDF(X,100) FOR X = -5 .05 5 AND 
    PLOT PNRPDF(X,50) FOR X = -5 .05 5 AND 
    PLOT PNRPDF(X,20) FOR X = -5 .05 5 AND 
    PLOT PNRPDF(X,5) FOR X = -5 .05 5 AND 
    PLOT PNRPDF(X,1) FOR X = -5 .05 5 AND 
    PLOT PNRPDF(X,0.5) FOR X = -5 .05 5 AND 
    PLOT PNRPDF(X,0.2) FOR X = -5 .05 5 AND 
    PLOT PNRPDF(X,0.1) FOR X = -5 .05 5 
        
    plot generated by sample program

Date created: 11/13/2002
Last updated: 4/4/2003
Please email comments on this WWW page to alan.heckert@nist.gov.