Re: [Help-gsl] Computation of gsl_sf_hyperg_1F1 fails for some values

[Daniel Schury]

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Am 10.05.2013 13:58, schrieb Sam Mason:
> On 10 May 2013 12:20, Daniel Schury <address@hidden> wrote:
>>> Is that double negation really needed? Seems redundant, or am I
>>> missing something?
>> I don't know where the double minus came from, but the third parameter
>> is in fact -1.0/2.0*pow((E1-x)/dE,2.0)). Then The value should be
>> something around 457.
> 
> If I evaluate the above in Mathematica (v8) with the values you gave
> before I get 1895.95 back; not sure why we're getting different
> answers.  Then again I don't have any experience of these
> hypergeometric functions so can't suggest much to help here—sorry!
Yes, you're right, I reported the wrong number.

> 
>>> You be better off reporting the actual values of a, b and x that
>>> caused the program to crash.  When you printed these out you may
>>> notice that something strange is happening.
>> The given values _are_ values I got problems with.
> 
> No, you're doing some calculations.  If you reported:
>   gsl_sf_hyperg_1F1(-1.045, 0.5, -706.88)
> then things would be clearer.
Ok, now I know what you mean. Does not change anything, program crashes.

> 
>> Interestingely, the last time I got a new error message: "R6025 - pure
>> virtual function call" But the description given by microsoft
>> (http://support.microsoft.com/kb/125749/en-us) doesn't help me.
> 
> This is a C++ error message; something has gone wrong with your class
> hierarchy; you need to look at your C++ code as this isn't anything to
> do with the GSL.  Maybe the wrappers from Origin are breaking
> something?
Maybe. Have you tried the calculation not only with the wrong double
minus, but with only one minus? If it works for you, I think I should
turn to the Origin support, as it seems to be a problem with their binaries.

- -- 
Freundliche Grüße
Daniel Schury
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