Looks like a bug. evalf() should work. Can you open an issue for it in the SymPy issue tracker?
Aaron Meurer On Tue, May 16, 2017 at 2:17 PM, Carlos Bouthelier Madre <[email protected]> wrote: > Hi, I am trying to compute an integral of a function f that has no > primitive, I have used Integral(f,(Tita1, 0, pi/2).(Tita2,0,pi/2)), because > I wanted to be able to define it and operate with it before evaluating it. > The problem is that when I try to use .evalf(), it won't give me a float > number, just an expression of the integral divided in several sums of the > same integral within different intervals. > > The expression of the integral is > ZE=16.0*Integral(4*Integral(8.0*(194.818182068005*(-sqrt(0.25*cos(Tita1)**2 > + 1) + sqrt(0.25*cos(Tita2)**2 + 1))*(sqrt(0.25*cos(Tita1)**2 + 1) + > sqrt(0.25*cos(Tita2)**2 + 1))*exp(1.5*sqrt(0.25*cos(Tita1)**2 + 1) - > 0.5*sqrt(0.25*cos(Tita2)**2 + 1)) - > 194.818182068005*(sqrt(0.25*cos(Tita1)**2 + 1) - sqrt(0.25*cos(Tita2)**2 + > 1))**2*exp(0.5*sqrt(0.25*cos(Tita1)**2 + 1) - 0.5*sqrt(0.25*cos(Tita2)**2 + > 1)) + 194.818182068005*(sqrt(0.25*cos(Tita1)**2 + 1) - > sqrt(0.25*cos(Tita2)**2 + 1))**2*exp(1.5*sqrt(0.25*cos(Tita1)**2 + 1) + > 0.5*sqrt(0.25*cos(Tita2)**2 + 1)) + > 194.818182068005*(sqrt(0.25*cos(Tita1)**2 + 1) - sqrt(0.25*cos(Tita2)**2 + > 1))*(sqrt(0.25*cos(Tita1)**2 + 1) + sqrt(0.25*cos(Tita2)**2 + > 1))*exp(0.5*sqrt(0.25*cos(Tita1)**2 + 1) + 0.5*sqrt(0.25*cos(Tita2)**2 + > 1)))*exp(-1.0*sqrt(0.25*cos(Tita1)**2 + 1))/((sqrt(0.25*cos(Tita1)**2 + 1) - > sqrt(0.25*cos(Tita2)**2 + 1))**2*(sqrt(0.25*cos(Tita1)**2 + 1) + > sqrt(0.25*cos(Tita2)**2 + 1))*sqrt(0.25*cos(Tita1)**2 + > 1)*sqrt(0.25*cos(Tita2)**2 + 1)), (Tita1, 0, 1.5707963267949)), (Tita2, 0, > 1.5707963267949)) > > What could I use to evaluate it ? How could I define it to make it work? > > In fact, I have substituted some other variables in the expression of ZE, so > it can compute the Integral. It would also be useful to know how to plot > ZE(x), if x was the unsubstitude variable inside the previous integral. > > > Thanks in advance > > -- > 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 https://groups.google.com/group/sympy. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sympy/6d80f23d-4e40-4e97-beb4-607e1a72ee43%40googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- 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 https://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/CAKgW%3D6%2BqJTR%3Dcc08_F-Ejwrv5AXbv2wC9RXJMSPGLOd-1WpXdw%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
