Re: [Scilab-users] Comparison of SCILAB to other Analytical Applications
May be this paper helps a little bit. Kind regards Klaus -Ursprüngliche Nachricht- Von: users [mailto:users-boun...@lists.scilab.org] Im Auftrag von Beck, Michel Gesendet: Montag, 15. Dezember 2014 20:46 An: users@lists.scilab.org Betreff: [Scilab-users] Comparison of SCILAB to other Analytical Applications Hi Jeff, I work for a large Energy Company in North America and we are finally trying to get scientific in our choice of analytical software (for about 10-20 users). Would you please point me to sources where I can find information on the Pros and Cons of SCILAB to fill in the attached RFI?. Thank you very much. Michel Email Disclaimer The information contained in or attached to this email is intended only for the use of the addressee. If you are not the intended recipient of this email, or a person responsible for delivering it to the intended recipient, you are strictly prohibited from disclosing, copying, distributing, or retaining this email or any part of it. It may contain information which is confidential and/or covered by legal, professional or other privilege under applicable law. If you have received this email in error, please notify us immediately by return email. The views expressed in this email are not necessarily the views of Centrica plc, nor its North American subsidiaries, and the said companies and their respective directors, officers and employees make no representation, nor accept any liability, regarding its accuracy or completeness, unless expressly stated to the contrary. FreeOpenSourceSoftwareAnAlternative2EngineeringStudents.pdf Description: Adobe PDF document ___ users mailing list users@lists.scilab.org http://lists.scilab.org/mailman/listinfo/users
[Scilab-users] Problem with function fitting
Hi, I have problem with fitting function to measured data using scilab. I tried scilab function datafit(), lsqrsolve(), leastsq() but none returns me a proper result or can't perform calculations. //I have measured data: xm;ym 2.0;99.9449173761 1.0;99.8097145719 0.5;97.9769654482 0.25;36.4046069104 0.1;1.4872308463 0.071;0.5207811718 0.063;0.3705558338 //Script used to fit data miny=min(ym); maxy=max(ym); minx=min(xm); maxx=max(xm); Zz=[xm;ym]; //Function describing problem (I want to find best fit by finding n()). function g1=f1(x, n) g1 = miny+((maxy-miny) ./((1+(n(1).*(x ./n(2)).^n(3))+(1-n(1)).*((x ./n(2)).^n(4.^n(5)) endfunction function e = G(n,z) xm = z(1) ym = z(2) e = ym - f1(xm,n) endfunction n0 = [1 ; 1; 1; 1; 1] [n0_opt,err] = datafit(G,Zz,n0) After calling function scilab returns me error: Variable returned by scilab argument function is incorrect. I tried to find solution for this problem in scilab mailing lists and tried some posted scripts and advices but I can't localize problem. Łukasz -- View this message in context: http://mailinglists.scilab.org/Problem-with-function-fitting-tp4031546.html Sent from the Scilab users - Mailing Lists Archives mailing list archive at Nabble.com. ___ users mailing list users@lists.scilab.org http://lists.scilab.org/mailman/listinfo/users
Re: [Scilab-users] Problem with function fitting
Your problem comes from the fact that for some values of n the computed value of e are complex values (some negative values to a non integer exponent. This can be made obvious with the following function function e = G(n,z) xm = z(1) ym = z(2) e = ym - f1(xm,n) if ~isreal(e) then pause,end endfunction The solution depends on the problem you want to solve. for example one can replage G by function e = G(n,z) xm = z(1) ym = z(2) e = ym - f1(xm,n) e=real(e*e') endfunction Serge Steer Le 17/12/2014 18:53, Maihem a écrit : Hi, I have problem with fitting function to measured data using scilab. I tried scilab function datafit(), lsqrsolve(), leastsq() but none returns me a proper result or can't perform calculations. //I have measured data: xm;ym 2.0;99.9449173761 1.0;99.8097145719 0.5;97.9769654482 0.25;36.4046069104 0.1;1.4872308463 0.071;0.5207811718 0.063;0.3705558338 //Script used to fit data miny=min(ym); maxy=max(ym); minx=min(xm); maxx=max(xm); Zz=[xm;ym]; //Function describing problem (I want to find best fit by finding n()). function g1=f1(x, n) g1 = miny+((maxy-miny) ./((1+(n(1).*(x ./n(2)).^n(3))+(1-n(1)).*((x ./n(2)).^n(4.^n(5)) endfunction function e = G(n,z) xm = z(1) ym = z(2) e = ym - f1(xm,n) endfunction n0 = [1 ; 1; 1; 1; 1] [n0_opt,err] = datafit(G,Zz,n0) After calling function scilab returns me error: Variable returned by scilab argument function is incorrect. I tried to find solution for this problem in scilab mailing lists and tried some posted scripts and advices but I can't localize problem. Łukasz -- View this message in context: http://mailinglists.scilab.org/Problem-with-function-fitting-tp4031546.html Sent from the Scilab users - Mailing Lists Archives mailing list archive at Nabble.com. ___ users mailing list users@lists.scilab.org http://lists.scilab.org/mailman/listinfo/users ___ users mailing list users@lists.scilab.org http://lists.scilab.org/mailman/listinfo/users
Re: [Scilab-users] Comparison of SCILAB to other Analytical Applications
To that I would add that Scilab works just fine on Windows -- or at least it has in my experience (I'm using a Linux machine). On Tue, 2014-12-16 at 19:35 +0100, Klaus Rohe wrote: May be this paper helps a little bit. Kind regards Klaus -Ursprüngliche Nachricht- Von: users [mailto:users-boun...@lists.scilab.org] Im Auftrag von Beck, Michel Gesendet: Montag, 15. Dezember 2014 20:46 An: users@lists.scilab.org Betreff: [Scilab-users] Comparison of SCILAB to other Analytical Applications Hi Jeff, I work for a large Energy Company in North America and we are finally trying to get scientific in our choice of analytical software (for about 10-20 users). Would you please point me to sources where I can find information on the Pros and Cons of SCILAB to fill in the attached RFI?. Thank you very much. Michel Email Disclaimer The information contained in or attached to this email is intended only for the use of the addressee. If you are not the intended recipient of this email, or a person responsible for delivering it to the intended recipient, you are strictly prohibited from disclosing, copying, distributing, or retaining this email or any part of it. It may contain information which is confidential and/or covered by legal, professional or other privilege under applicable law. If you have received this email in error, please notify us immediately by return email. The views expressed in this email are not necessarily the views of Centrica plc, nor its North American subsidiaries, and the said companies and their respective directors, officers and employees make no representation, nor accept any liability, regarding its accuracy or completeness, unless expressly stated to the contrary. ___ users mailing list users@lists.scilab.org http://lists.scilab.org/mailman/listinfo/users -- Tim Wescott www.wescottdesign.com Control Communications systems, circuit software design. Phone: 503.631.7815 Cell: 503.349.8432 ___ users mailing list users@lists.scilab.org http://lists.scilab.org/mailman/listinfo/users
Re: [Scilab-users] Problem with function fitting
Thanks for answer but it seems that implementation of this only allowed to avoid error cause calculated parameters still don't fit to data. Parameters calculated by implementation real on e gives fit parameters: n(1)= 1.264264 n(2)= - 0.1891816 n(3)= 1.6592188 n(4)= 0.9977104 n(5)= 1.0404815 but this parameters are wrong. For example I fitted this equation using Gnuplot and I recived: n(1)= 0.960002 n(2)= 0.331008 n(3)= -8.26945 n(4)= -1.9777 n(5)= 0.423854 and this results from gnuplot fits this function to data I'm little confused why I can't receive similar solution from scilab Łukasz -- View this message in context: http://mailinglists.scilab.org/Problem-with-function-fitting-tp4031546p4031549.html Sent from the Scilab users - Mailing Lists Archives mailing list archive at Nabble.com. ___ users mailing list users@lists.scilab.org http://lists.scilab.org/mailman/listinfo/users
Re: [Scilab-users] Problem with function fitting
Thanks for help, now it looks fine Łukasz -- View this message in context: http://mailinglists.scilab.org/Problem-with-function-fitting-tp4031546p4031551.html Sent from the Scilab users - Mailing Lists Archives mailing list archive at Nabble.com. ___ users mailing list users@lists.scilab.org http://lists.scilab.org/mailman/listinfo/users
