Function Weibull(Shape, Lowerbound, Scale)

Weibull

The function Weibull draws a random value from a Weibull distribution.

Weibull(
       Shape,       ! (input) numerical expression
       Lowerbound,  ! (optional) numerical expression
       Scale        ! (optional) numerical expression
       )

Arguments

Shape

A scalar numerical expression \(> 0\).

Lowerbound

A scalar numerical expression.

Scale

A scalar numerical expression \(> 0\).

Return Value

The function Weibull returns a random value drawn from a Weibull distribution with shape Shape lower bound Lowerbound, and scale Scale.

Note

The prototype of this function has changed with the introduction of AIMMS 3.4. In order to run models that still use the original prototype, the option Distribution_compatibility should be set to Aimms_3_0. In the original function Weibull(Lowerbound, Shape, Scale), the arguments were ordered differently.

Graph

../../_images/weibull.png

A graph with:

  • a histogram for 100 experiments of drawing from distribution Weibull(5,0,5), and

  • the DistributionDensity for Weibull(5,0,5)

Example

The code:

option seed := 1234 ;
_p_draw := Weibull( 0.3, 0, 100 )  ;
_p_pointDensity := DistributionDensity( Weibull( 0.3, 0, 100  ), 20 );

block where listing_number_precision := 6 ;
    display _p_draw, _p_pointDensity ;
endblock ;

will produce

_p_draw := 5.483940 ;
_p_pointDensity := 0.004994 ;

in the listing file.

References