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Draw random numbers from a normal distribution in an Ocean script

Alice92

Hello,

I want to study the effect of the parameter variabilty of a verilogA component. I would like to draw random numbers from a normal distribution when using desVar in my Ocean script.

How could I do this?

Thank you very much for your help

Parents

  • I didn't see so much in the skill manual about generating random numbers from a normal distribution but you could use the Box-Mueller transform to get a sigma=1.0, mean=0.0 normally distributed random variable.  Then just scale by the sigma you want and offset by the mean you want.

    procedure( MYrandNorm() 
    let((w, u1, u2, x1, x2)
    w = 2.0
    while( w >= 1.0

    ;; what we really want here is something uniformly distributed on [0,1]

    u1=1.0*random(m.MAX_INT) / m.MAX_INT

    u2=1.0*random(m.MAX_INT) / m.MAX_INT

    x1 = 2.0 * u1 - 1.0

    x2 = 2.0 * u2 - 1.0
    w = x1*x1 + x2*x2
    )
    w = sqrt( (-2.0 * log(w) ) / w)
    y1 = x1*w
    y2 = x2*w

    ) ; ** let **
    )

Reply

  • I didn't see so much in the skill manual about generating random numbers from a normal distribution but you could use the Box-Mueller transform to get a sigma=1.0, mean=0.0 normally distributed random variable.  Then just scale by the sigma you want and offset by the mean you want.

    procedure( MYrandNorm() 
    let((w, u1, u2, x1, x2)
    w = 2.0
    while( w >= 1.0

    ;; what we really want here is something uniformly distributed on [0,1]

    u1=1.0*random(m.MAX_INT) / m.MAX_INT

    u2=1.0*random(m.MAX_INT) / m.MAX_INT

    x1 = 2.0 * u1 - 1.0

    x2 = 2.0 * u2 - 1.0
    w = x1*x1 + x2*x2
    )
    w = sqrt( (-2.0 * log(w) ) / w)
    y1 = x1*w
    y2 = x2*w

    ) ; ** let **
    )

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