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Dataplot Vol 2 Vol 1

LDEPPF

Name:
    LDEPPF (LET)
Type:
    Library Function
Purpose:
    Compute the standard form of the log double exponential (also known as the log Laplace distribution) percent point function.
Description:
    The standard form of the log double exponential distribution has the following percent point function:

      G(p) = (2*p)**(1/alpha)     0 <= p < LDECDF(1,alpha); alpha > 0

      G(p) = (2*(1-p))**(-1/alpha)  LDECDF(1,alpha) <= p < 1; alpha > 0

    where LDECDF is the cumulative distribution function of the log double exponential distribution.

Syntax:
    LET <y> = LDEPPF(<p>,<alpha>)           <SUBSET/EXCEPT/FOR qualification>
    where <p> is a variable, a number, or a parameter;
              <y> is a variable or a parameter (depending on what <p> is) where the computed log double exponential ppf value is saved;
              <alpha> is a variable, a number, or a parameter that specifies the shape parameter;
    and where the <SUBSET/EXCEPT/FOR qualification> is optional.
Examples:
    LET A = LDEPPF(0.9,2)
    LET X2 = LDEPPF(P1,0.5)
Default:
    None
Synonyms:
    None
Related Commands:
    LDECDF = Compute the double exponential cumulative distribution function.
    LDEPDF = Compute the double exponential probability density function.
    DEXPDF = Compute the double exponential cumulative distribution function.
    EXPPDF = Compute the exponential cumulative distribution function.
    WEIPDF = Compute the Weibull cumulative distribution function.
    EV1PDF = Compute the extreme value type I cumulative distribution function.
    CHSPDF = Compute the chi-square cumulative distribution function.
Reference:
    "Continuous Univariate Distributions: Volume 2", 2nd Ed., Johnson, Kotz, and Balakrishnan, John Wiley, 1994, page 192.
Applications:
    Distributional Modeling
Implementation Date:
    2001/10
Program:
        MULTIPLOT 2 2 
        MULTIPLOT CORNER COORDINATES 5 5 95 95 
        TITLE AUTOMATIC 
        PLOT LDEPPF(P,0.5)  FOR P = 0.01 0.01 0.99 
        PLOT LDEPPF(P,1)  FOR P = 0.01 0.01 0.99 
        PLOT LDEPPF(P,2)  FOR P = 0.01 0.01 0.99 
        PLOT LDEPPF(P,5)  FOR P = 0.01 0.01 0.99 
        END OF MULTIPLOT 
        
    plot generated by sample program

Date created: 10/9/2001
Last updated: 4/4/2003
Please email comments on this WWW page to alan.heckert@nist.gov.