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Why no Bessel functions in formula editor?

yvesprairie

Community Trekker

Joined:

Nov 25, 2014

I posted this question earlier in August. One person responded (thank you!) that one could write the code in JSL. Although this solution might be viable, it seems difficult to imagine this hasn't been implemented directly into JMP, it seems such an obvious function to add to the lot. I would like to know whether JMP could consider doing this rather simple addition in a future update?

Many thanks, Yves

2 REPLIES
ms

Super User

Joined:

Jun 23, 2011

Maybe the Bessel functions are not needed by the typical JMP user and therefore have not been requested. Until now. I suggest you send a feature request to support@jmp.com​ to increase the chance for it to happen.

Otherwise, the Bessel functions are straightforward to implement by combining current functions.

For example:

Names Default To Here(1);

//Bessel function of first kind (J)

BesselJ = Function({x, alpha},

    Summation(m = 0, 50, (-1) ^ m / Factorial(m) / Gamma(m + alpha + 1) * (x / 2) ^ (2 * m + alpha))

);

// Example graph

alpha = 0;

New Window("Bessel example",

    y = Graph Box(

        Y Scale(-1, 1),

        X Scale(0, 30),

        XName("x"),

        Y Function(BesselJ(x, alpha), x);

        Text({25, 0.8}, "\!U03B1=", Round(alpha, 2));

    ),

    H List Box(Text Box(" \!U03B1"), Slider Box(0, 10, alpha, y << reshow))

);


yvesprairie

Community Trekker

Joined:

Nov 25, 2014

Many thanks for this MS. I have followed your advice and sent a message to feature request. I will modify your script to also compute modified Bessel functions! Thanks again, Yves