Re: [Scilab-users] improve accuracy of roots

2019-01-15 Thread Federico Miyara
rt.thalesgroup.com/ump-cnrs-thales http://www.research.thalesgroup.com -Message d'origine- De : users [mailto:users-boun...@lists.scilab.org] De la part de Federico Miyara Envoyé : samedi 12 janvier 2019 07:52 À : Users mailing list for Scilab Objet : Re: [Scilab-users] improve accur

Re: [Scilab-users] improve accuracy of roots

2019-01-15 Thread Stéphane Mottelet
...@lists.scilab.org] De la part de Federico Miyara Envoyé : samedi 12 janvier 2019 07:52 À : Users mailing list for Scilab Objet : Re: [Scilab-users] improve accuracy of roots Denis, I've found the correction here, https://en.wikipedia.org/wiki/Newton%27s_method It is useful to accelerate

Re: [Scilab-users] improve accuracy of roots

2019-01-14 Thread Federico Miyara
e Federico Miyara Envoyé : samedi 12 janvier 2019 07:52 À : Users mailing list for Scilab Objet : Re: [Scilab-users] improve accuracy of roots Denis, I've found the correction here, https://en.wikipedia.org/wiki/Newton%27s_method It is useful to accelerate convergence in case of multiple ro

Re: [Scilab-users] improve accuracy of roots

2019-01-14 Thread CRETE Denis
ers [mailto:users-boun...@lists.scilab.org] De la part de Federico > Miyara > Envoyé : jeudi 10 janvier 2019 00:32 > À : users@lists.scilab.org > Objet : [Scilab-users] improve accuracy of roots > > > Dear all, > > Consider this code: > > // Define polynomial variable >

Re: [Scilab-users] improve accuracy of roots

2019-01-11 Thread Federico Miyara
o for R=(3+p)^4, again with an accuracy on the roots of a ~2E-8. HTH Denis -Message d'origine- De : users [mailto:users-boun...@lists.scilab.org] De la part de Federico Miyara Envoyé : jeudi 10 janvier 2019 00:32 À : users@lists.scilab.org Objet : [Scilab-users] improve accuracy

Re: [Scilab-users] improve accuracy of roots

2019-01-11 Thread Federico Miyara
org Objet : [Scilab-users] improve accuracy of roots Dear all, Consider this code: // Define polynomial variable p = poly(0, 'p', 'roots'); // Define fourth degree polynomial R = (1 + p)^4; // Find its roots z = roots(R) The result (Scilab 6.0.1) is z = -1.0001

Re: [Scilab-users] improve accuracy of roots

2019-01-10 Thread Stéphane Mottelet
Federico Miyara Envoyé : jeudi 10 janvier 2019 00:32 À : users@lists.scilab.org Objet : [Scilab-users] improve accuracy of roots Dear all, Consider this code: // Define polynomial variable p = poly(0, 'p', 'roots'); // Define fourth degree polynomial R = (1 + p)^4; // Find

Re: [Scilab-users] improve accuracy of roots

2019-01-10 Thread CRETE Denis
e roots of a ~2E-8. HTH Denis -Message d'origine- De : users [mailto:users-boun...@lists.scilab.org] De la part de Federico Miyara Envoyé : jeudi 10 janvier 2019 00:32 À : users@lists.scilab.org Objet : [Scilab-users] improve accuracy of roots Dear all, Consider this code: // De

[Scilab-users] improve accuracy of roots

2019-01-09 Thread Federico Miyara
Dear all, Consider this code: // Define polynomial variable p = poly(0, 'p', 'roots'); // Define fourth degree polynomial R = (1 + p)^4; // Find its roots z = roots(R) The result (Scilab 6.0.1) is z = -1.0001886 -1. + 0.0001886i -1. - 0.0001886i -0.9998114 It should be somethin