I have opened https://github.com/sympy/sympy/issues/8685 for this, and debugged the code a little bit and found the problem.
Aaron Meurer On Tue, Dec 23, 2014 at 5:02 PM, Aaron Meurer <[email protected]> wrote: > Looks like you found a bug. I get the right result with meijerg=True, > which forces it to use that algorithm. > > Aaron Meurer > > On Tue, Dec 23, 2014 at 1:46 PM, Groover <[email protected]> wrote: >> Hello, I am clearly making a stupid mistake, but what? >> >> Arc length calculation: >> >> x = Symbol('x') >> >> formula = 2 * x**2 >> >> d = diff(formula, x) >> i = integrate(sqrt(1 + d**2), (x, 5.0, 10.0)) >> >> >> gives a result of 150.087 >> >> but changing the formula to this: >> >> formula = 0.26666 * x**2 >> >> gives a result of zero. In fact any coefficient less than one gives a result >> of zero. >> >> Thanks, Andy >> >> -- >> 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. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/sympy/a04d07c6-5dfe-47dc-a90e-d89a7bae6165%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 http://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/CAKgW%3D6LT%2BNeCO6jfdV0wBBK1TARbej7P%3DRnYbN5QdR7QZQ%2Bbpw%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
