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Inverse binomial - Printable Version

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Inverse binomial - Richard Berler - 07-07-2013

1) On both my emulator and my physical unit, inverse binomial with p=.5 stored in j, n=10 stored in k for .005 yields 10. I was expecting 0 or possibly 1.

.006 correctly produces an answer of 1.

2) On my emulator when trying large n such as 1 E 06, inverse binomial p=.5, n (k)=1 E 06 for .75 produces 500337. My physical unit produces "reset". The physical unit will come up with a proper result for .75=501288.

2) might be due to older version (3.1 3278)

Re: Inverse binomial - Richard Berler - 07-07-2013

Physical unit produces correct answer of 501288 for .995 (not the .75 that I accidentally reported).

Re: Inverse binomial - Marcus von Cube, Germany - 07-08-2013

I'm not the one to answer your question about the proper results, but "reset" is definitely not the intended answer. It looks like another internal stack overflow issue or the like.

Re: Inverse binomial - Nick_S - 07-08-2013

Using the R statistical package I get a value of 1 for your first example



and 500337 for your second example




Edited: 10 July 2013, 11:28 a.m.

Re: Inverse binomial - Walter B - 07-08-2013

Hi Richard,

Thanks for reporting. Your observation 1) is definitively a bug. Even 0.0051 Binom^(-1) returns 1. I guess the cause is some internal rounding or truncating.


Re: Inverse binomial - Paul Dale - 07-08-2013

I think we should fix the memory/stack overflow/corruption bug 2 before jumping to any conclusions about the cause of 1.

- Pauli

Re: Inverse binomial - Walter B - 07-08-2013

I concur. Go ahead!


Re: Inverse binomial - Marcus von Cube, Germany - 07-09-2013

The "Reset" proved to be the watch dog kicking in. I've added another call to service the watch dog in the code and the "Reset" seems to be gone. Maybe Pauli can find a way to speed up the calculation a little. It just took too long...