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Student Support Forum: 'Bug in plot involving hypergeometric function' topicStudent Support Forum > General > Archives > "Bug in plot involving hypergeometric function"

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05/19/13 5:18pm

This Plot multiplied very large numbers times very small numbers, which can be a source of precision problems.

Converting all the parameters to high-precision and keeping the precision high throughout the calculation works. The simple sub-method is to make the parameters exact (Integers and Rationals) and convert to high-precision floating-point just before plotting. See the attached notebook.

rat[x_] = Rationalize[ E^(1.21089 x) *
Hypergeometric2F1[1, 1.0093, 1.6741, -2.385 E^(1.26501 x)], 0]

Plot[rat[x], {x,-10,80}, WorkingPrecision -> 50]


The amount of precision that Hypergeometric2F1 looses for mid-size x may be a fixable problem. I reported it to developers.


Attachment: 497352aPlotProductHypergeometricExponential.nb, URL: ,

Subject (listing for 'Bug in plot involving hypergeometric function')
Author Date Posted
Bug in plot involving hypergeometric function Black Light 05/19/13 07:25am
Re: Bug in plot involving hypergeometric function Forum Modera... 05/19/13 5:18pm
Re: Re: Bug in plot involving hypergeometric fu... Black Light 05/20/13 05:35am
Re: Re: Bug in plot involving hypergeometric fu... Black Light 05/22/13 04:01am
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