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Dataplot Vol 2 Vol 1

WALCHAZ

Name:
    WALCHAZ (LET)
Type:
    Library Function
Purpose:
    Compute the Wald cumulative hazard function with shape parameter gamma.
Description:
    The Wald distribution has the following cumulative hazard function:

      H(x) = -LOG[1 - WALCDF(x,gamma)]      x >= 0, gamma > 0

    where gamma is the shape parameter and WALCDF is the cumulative distribution function of the Wald distribution function respectively.

Syntax:
    LET <y> = WALCHAZ(<x>,GAMMA)             <SUBSET/EXCEPT/FOR qualification>
    where <x> is a variable or a parameter containing positive values;
                  <y> is a variable or a parameter (depending on what <x> is) where the computed Wald cumulative hazard values are stored;
                  <GAMMA> is a positive number or parameter that specifies the shape parameter;
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
    LET A = WALCHAZ(3,10)
    LET A = WALCHAZ(A1,10)
    LET X2 = WALCHAZ(X1,10)
Default:
    None
Synonyms:
    None
Related Commands:
    WALCDF = Compute the Wald cumulative distribution function.
    WALPDF = Compute the Wald probability density function.
    WALPPF = Compute the Wald percent point function.
    WALHAZ = Compute the Wald hazard function.
    CHSPDF = Compute the chi-square probability density function.
    FPDF = Compute the F probability density function.
    NORPDF = Compute the normal probability density function.
    TPDF = Compute the T probability density function.
    WEIPDF = Compute the Weibull probability density function.
    FLPDF = Compute the Fatigue Life probability density function.
    IGPDF = Compute the Inverse Gaussian probability density function.
    RIGPDF = Compute the Reciprocal Inverse Gaussian probability density function.
Reference:
    "Continuous Univariate Distributions: Volume 1", 2nd. Ed., Johnson, Kotz, and Balakrishnan, John Wiley, 1994.
Applications:
    Reliability Analysis
Implementation Date:
    1998/4
Program:
    TITLE AUTOMATIC 
    MULTIPLOT CORNER COORDINATES 5 5 95 95 
    MULTIPLOT 2 2 
    PLOT WALCHAZ(X,1) FOR X = 0.01 0.01 3
    PLOT WALCHAZ(X,2) FOR X = 0.5 0.01 2
    PLOT WALCHAZ(X,3) FOR X = 0.7 0.01 1.3
    PLOT WALCHAZ(X,0.5) FOR X = 0.1 0.01 3
    END OF MULTIPLOT 
        
    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.