They are linear equations, the coeficients are floating points ... the simpliest kind of linear equations for solving. For example
solve([2x + 2y + 3= 0 , 4.2x + 5y + 1 = 0 ... ] , solution_dict=True) Here's a real big one 165 unknowns with 165 equations that SAGE's solve runs at least 5 times faster than Sympy's solve: http://pastebin.com/cE87W9m3 On Friday, March 8, 2013 12:36:38 AM UTC-7, Aaron Meurer wrote: > > What kind of equations are these? Are they linear equations, or > polynomial? Are the coefficients rational, floating point, or > symbolic. Maybe you could paste an example somewhere. > > solve being slow is a real problem. To fix it, we need to figure out > what part is slowing it down, and either make it faster or figure out > if it can be removed for that computation. > > Aaron Meurer > > On Thu, Mar 7, 2013 at 10:57 PM, ThanhVu Nguyen > <[email protected] <javascript:>> wrote: > > I concur, the "solve in Sympy is very slow comparing to the "solve" > > function in Sage. Doesn't need to come up with any special example, > just > > try to solve over 20 unknowns and so and you will see the difference. > > > > One of my problem requires solving for 248 eqts for 164 unknowns. Here's > the > > time: with SAGE 4.5.1 : 82.8926379681 secs, with Sympy 0.7.2: > 557.724228144 > > secs. Both give the exact same solution so no problem on soundness. > > > > I don't like using Sage because it's inconvenient to ask the users to > > download the huge package, but my stuff relies on equation solvings so > I > > have to stick with Sage. > > > > > > > > On Sunday, February 24, 2013 3:15:27 AM UTC-7, Alessandro Bernardini > wrote: > >> > >> Hello, > >> > >> i have to solve systems of linear algebraic equations (nodal equations > >> from circuit theory). > >> I tried examples witch 7 unknowns and a lot of symbolic parameters: i > >> obtain 7 equations in the 7 unknowns (and with the symbolic > parameters). > >> Then i solve for the 7 unknowns: sympy solve simply runs "out of time". > >> For 3 unknowns in 3 equations the results are computed after a few > >> minutes. For 7 unknowns in 7 equations i had to stop the computation. > >> > >> Sage math does it in much lesser time. > >> > >> I have tried manual=True simplify=False and other options and i always > >> have the same performance problem. > >> > >> Can someone help ? > >> > >> Thanks > >> > > -- > > You received this message because you are subscribed to the Google > Groups > > "sympy" group. > > To unsubscribe from this group and stop receiving emails from it, send > an > > email to [email protected] <javascript:>. > > To post to this group, send email to [email protected]<javascript:>. > > > Visit this group at http://groups.google.com/group/sympy?hl=en. > > For more options, visit https://groups.google.com/groups/opt_out. > > > > > -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sympy?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
