Christian Hoffmann on Tue, 07 May 2013 23:43:05 +0200 |
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Re: silly long list of suggestions |
Am 15.04.13 19:52, schrieb Joerg Arndt:
Thanks for the swift reply. * Bill Allombert <Bill.Allombert@math.u-bordeaux1.fr> [Apr 15. 2013 18:24]:On Mon, Apr 15, 2013 at 05:49:57PM +0200, Joerg Arndt wrote: Hello Joerg, thanks for your suggestions.Pade approximant for series, see http://jjj.de/pari/pade.gpi (looks doable)Did you try bestappr and bestapprPade ?I was afraid I'd touch things actually possible already... ? bestapprPade(sin(x),5) %6 = (911*x^11 - 250734*x^9 + 29604960*x^7 - 1665195840*x^5 + 39178339200*x^3 - 250637587200*x)/(-8981280*x^4 - 2594592000*x^2 - 250637587200) Good!
This gives : ? bestapprPade(sin(x),5) *** at top-level: bestapprPade(sin(x), *** ^-------------------- *** not a function in function call on my machine: GP/PARI CALCULATOR Version 2.5.3 (released) i386 running darwin (x86-64/GMP-5.0.5 kernel) 64-bit version compiled: Mar 19 2013, gcc-4.7.1 (GCC) Christian
An option to have polynomials printed "constant
first". This is much neater in some cases, e.g., for rational generating functions.Well, you can convert your polynomial to a power series for display.Won't work with fractions of polynomials (as other things I suggested, there are workarounds; I only made such suggestions when I thought it would lead to more expressive Pari code).Option to have Vec(series) _not_ drop initial zeros.Try Vec(series,n)Second arg determines length of vector, not initial index. I'd like to be able to have ? Vec(x^3/(1-x)+O(x^6)) \\ give %4 = [0, 0, 0, 1, 1, 1] \\ and not %4 = [1, 1, 1] My usual workaround is v = Vec(x^3/(1-x)+O(x^6) +'c0); v[1] -= 'c0; v ... but that's at least a bit noisy.Cheers, Bill.Best, jj
-- Christian W. Hoffmann, CH - 8915 Hausen am Albis, Switzerland Rigiblickstrasse 15 b, Tel.+41-44-7640853 c-w.hoffmann@sunrise.ch, christian@echoffmann.ch, www.echoffmann.ch