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Version is Maxima 5.9.1
Hello
I had to interrupt maxima when it was at calculating the following integral:
(%i101) m(r,th);
2 2
(%o101) SQRT(z + 2 r rM (1 - COS(th)) + (rM - r) )
(%i102) F(d);
2
2 d0
4 A d0 (epsi - --- + 1) w
2
d
(%o102) - --------------------------
3
d
(%i103) integrate(1/m(th,r)^2*F(m(th,r))*z^2,th,0,%PI);
2 2 2 2
Is z - COS (r) rM + rM positive, negative, or zero?
pos;
2 2 2
Is z + (1 - COS (r)) rM positive, negative, or zero?
pos;
Maxima encountered a Lisp error:
Console interrupt.
Best wishes,
Jocelyn
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Version is Maxima 5.9.1
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sorry about the mess...
the functions are:
m(r,th):=sqrt(z^2+(rM-r)^2+2*rM*r*(1-cos(th)));
and
F(d):=-4*w/d*(d0/d)^2*(1+epsi-(d0/d)^2)*A;
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It does seem to loop. Not sure if it really does, because I didn't wait for very long.
Note, however, that all of the integrals are of the form 1/(th^2+a*th*b)^(n/2) where n is odd (5 or 7 here). Maxima can evaluate all of these integrals quite quickly. I think, but I'm not sure, that maxima is busy simplifying complicated intermediate expressions because the coefficients are not simple.
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What is the integrand? You have the function m(r,th), but the integral says m(th,r). Given the limits of 0 and %pi, I think your integrand is wrong. Did you really want m(r,th)?
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No additional information from poster.
Marking as Pending
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