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Dataplot Vol 2 Vol 1

DIWPPF

Name:
    DIWPPF (LET)
Type:
    Library Function
Purpose:
    Compute the discrete Weibull percent point function.
Description:
    The discrete Weibull distribution has the following percent point function:

      G(p;q,beta) = {LOG(1-p)/LOG(q)]**(1/beta)
 0 <= p < 1; 0 < q < 1;  beta > 0

    with q and beta denoting the shape parameters.

Syntax:
    LET <y> = DIWPPF(<p>,<q>,<beta>)
                            <SUBSET/EXCEPT/FOR qualification>
    where <p> is a positive integer variable, number, or parameter in the interval (0,1);
                <q> is a number, parameter, or variable in the range (0,1) that specifies the first shape parameter;
                <beta> is a number, parameter, or variable that specifies the second shape parameter;
                <y> is a variable or a parameter (depending on what <x> is) where the computed discrete Weibull ppf value is stored;
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
    LET A = DIWPPF(0.95,0.5,0.5)
    LET Y = DIWPPF(P,0.3,0.7)
    PLOT DIWPPF(P,0.6,0.4) FOR P = 0 0.01 0.99
Default:
    None
Synonyms:
    None
Related Commands:
    DIWCDF = Compute the discrete Weibull cumulative distribution function.
    DIWHAZ = Compute the discrete Weibull hazard function.
    DIWPDF = Compute the discrete Weibull probability mass function.
    GLSPDF = Compute the generalized logarithmic series probability mass function.
    WEIPDF = Compute the Weibull probability density function.
    LGNPDF = Compute the lognormal probability density function.
    EXPPDF = Compute the exponential probability density function.
    POIPDF = Compute the Poisson probability mass function.
    BINPDF = Compute the binomial probability mass function.
Reference:
    Johnson, Kemp, and Kotz (2005), "Univariate Discrete Distributions", Third Edition, Wiley, pp. 510-511.

    Nakagawa and Osaki (1975), "The Discrete Weibull Distribution", IEEE Transactions on Reliability, R-24, pp. 300-301.

Applications:
    Distributional Modeling
Implementation Date:
    2006/8
Program:
     
    title size 3
    tic label size 3
    label size 3
    legend size 3
    height 3
    x1label displacement 12
    y1label displacement 15
    .
    multiplot corner coordinates 0 0 100 95
    multiplot scale factor 2
    label case asis
    title case asis
    case asis
    tic offset units screen
    tic offset 3 3
    title displacement 2
    x1label Probability
    y1label X
    .
    xlimits 0 1
    major xtic mark number 6
    minor xtic mark number 3
    line blank
    spike on
    .
    multiplot 2 2
    .
    title Q = 0.3, Beta = 0.3
    plot diwppf(p,0.3,0.3) for p = 0  0.01  0.99
    .
    title Q = 0.5, Beta = 0.5
    plot diwppf(p,0.5,0.5) for p = 0  0.01  0.99
    .
    title Q = 0.7, Beta = 0.7
    plot diwppf(p,0.7,0.7) for p = 0  0.01  0.99
    .
    title Q = 0.9, Beta = 0.9
    plot diwppf(p,0.9,0.9) for p = 0  0.01  0.99
    .
    end of multiplot
    .
    justification center
    move 50 97
    text Percent Point Functions for Discrete Weibull
        
    plot generated by sample program

Date created: 11/16/2006
Last updated: 11/16/2006
Please email comments on this WWW page to alan.heckert@nist.gov.