Forums before death by AOL, social media and spammers... "We can't have nice things"
|    sci.math.symbolic    |    Symbolic algebra discussion    |    10,432 messages    |
[   << oldest   |   < older   |   list   |   newer >   |   newest >>   ]
|    Message 10,290 of 10,432    |
|    Sam Blake to clicl...@freenet.de    |
|    Re: Rule-based integration    |
|    04 Feb 23 02:00:15    |
      From: samuel.thomas.blake@gmail.com              On Friday, July 23, 2010 at 7:52:06 AM UTC+10, clicl...@freenet.de wrote:       > "Nasser M. Abbasi" schrieb:       > >       > > On 7/21/2010 11:08 AM, clicl...@freenet.de wrote:       > > >       > > > FriCAS has been working on       > > >       > > > INT(SQRT(SQRT(x^4+1)+x^2)/((x+1)^2*SQRT(x^4+1)),x)       > > >       > > > for thirty days now!       > > >       > >       > > How do you know it is actually doing something useful and not stuck in > a       loop?       > >       > > Does FriCAS has an indicator saying it is actually doing different       > > things? Do you have tracing on?       > >       > I have to pass these questions on to Waldek Hebisch, who announced this       > calculation one month ago - I just provided the integral.       > > What possibly it can be doing in these 30 days? trying what? is risch       > > algorithm used here?       > >       > > Let us know when and if it completes ;)       > >       > Waldek seemed to be confident that FriCAS would ultimately be       > successful, but he has warned already about running times reaching weeks       > or months. The latter prediction is already borne out!       > Are you and Vladimir advocating to show mercy by terminating this       > calculation? There are no objections from my side, but it is for Wakdek       > to decide.       > Martin.              12 years late to this thread - Mathematica 13.2 get this one in under 5       seconds on my laptop:              In[5296]:= $Version       Out[5296]= "13.2.0 for Mac OS X x86 (64-bit) (November 18, 2022)"              In[5297]:= Integrate[Sqrt[x^2 + Sqrt[1 + x^4]]/((1 + x)^2 Sqrt[1 + x^4]), x]              Out[5297]= 1/2 ((-1 - 2 x^4 - Sqrt[1 + x^4] - x^2 (1 + 2 Sqrt[1 + x^4]))/((1 +       x) (x^2 + Sqrt[1 + x^4])^(3/2)) +        ArcTan[Sqrt[1 + Sqrt[2]] Sqrt[x^2 + Sqrt[1 + x^4]]]/Sqrt[-1 + Sqrt[2]] -        Sqrt[1 + Sqrt[2]]ArcTan[(Sqrt[2 (-1 + Sqrt[2])] x Sqrt[x^2 + Sqrt[1 +       x^4]])/(        1 + x^2 + Sqrt[1 + x^4])] - ArcTanh[Sqrt[-1 + Sqrt[2]] Sqrt[x^2 + Sqrt[1       + x^4]]]/Sqrt[        1 + Sqrt[2]] + Sqrt[-1 + Sqrt[2]]ArcTanh[(Sqrt[2 (1 + Sqrt[2])] x Sqrt[x^2       + Sqrt[1 + x^4]])/(1 + x^2 + Sqrt[1 + x^4])])              If the time constraint to IntegrateAlgebraic in increased then it can also       compute              Integrate[Sqrt[x^2 + Sqrt[1 + x^4]]/((a x + b)^2 Sqrt[1 + x^4]), x]              --- SoupGate-Win32 v1.05        * Origin: you cannot sedate... all the things you hate (1:229/2)    |
[   << oldest   |   < older   |   list   |   newer >   |   newest >>   ]
(c) 1994, bbs@darkrealms.ca