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Exponential integral function
Hello,
I'm looking for special function (exponential integral function,
Ei(x)). I found nothing about this function with Scilab. How can I
calculate it?
Thanks,
Jean-Yves
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Reply
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 Jean
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3/1/2011 5:34:29 PM |
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On Mar 1, 11:34=A0am, Jean-Yves Baudais
<jeanyves.baud...@insaminusrennesdotfr.invalid> wrote:
> Hello,
>
> =A0 =A0I'm looking for special function (exponential integral function,
> Ei(x)). I found nothing about this function with Scilab. How can I
> calculate it?
> Thanks,
> Jean-Yves
Hi, I checked around the new NIST Digital Library of Mathematical
Functions seems to point to expensive article downloads; whereas the
original NBS Handbook of mathematical functions has rational
polynomial approximations of 10^-4 and 10^-7 printed. I mention
these because they are simple and fast. If you look at either book
you can use Scilab to do the defining integration; but that will
probably be slower.
If your don't have the older book I can cut and paste the formula, or
there is a copy on the net.
Ray
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RRogers
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3/2/2011 2:48:40 PM
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1 Replies
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