Timeline for Is it possible to get analytic solution of this integral?
Current License: CC BY-SA 4.0
11 events
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| Oct 28 at 14:23 | comment | added | Greg Hurst |
Very nice (+1). To be careful you could call PowerExpand[_, Assumptions -> 0 < t < x] to prevent blind collapsing of powers, etc. In this case it's equivalent to your call though.
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| Oct 28 at 9:29 | vote | accept | miles | ||
| Oct 27 at 18:57 | comment | added | Michael E2 | @azerbajdzan In a similar vein, adding a redundant assumption in a different form to Simplify or Reduce sometimes helps, because, I suppose, they don't always derive and apply all the possible conclusions from the givens. | |
| Oct 27 at 18:01 | comment | added | Michael E2 | @miles I'm using V14.1 for Mac ARM. Integrate[]'s abilities changes often between versions. | |
| Oct 27 at 18:00 | comment | added | Michael E2 |
@azerbajdzan Nope. Specific examples have not stuck in my memory and such edge cases have not come up very often. There may be some on site among the 750+ answers I've given that involve Integrate. Further, what made a difference in, say, V8 no longer made a difference perhaps in V10 or later. x > t > 0 is just a way to make available the assumption that the path of integration is real. The person who might know is Daniel Lichtblau. Maybe it has become part of the internal code, and over the next few years I will realize that it hasn't helped. Or not.
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| Oct 27 at 18:00 | comment | added | miles | @MichaelE2 I don't know why I can't get the output that you shown | |
| Oct 27 at 17:41 | comment | added | azerbajdzan |
@MichaelE2 Do you have an example when x > 0 fails but x > t > 0 is successful?
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| Oct 27 at 16:35 | comment | added | Michael E2 |
@azerbajdzan You may find sometimes that x > t > 0 performs better than just x > 0. It may not make logical sense to you, but I have observed it to make a difference in what the internal code produces. And I have observed adding it does not always yield the simplification it should. Further, the edge cases change with each version update, naturally. It may be eventually in some version, it won't make a difference; but I think it should, since the path from 0 to x may be complex, even if x is real. I pass these remarks along as a trick one might try when x > 0 is insufficient.
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| Oct 27 at 16:20 | comment | added | Nasser |
Good trick with PowerExpand Will remove my answer using numerical integration as Mathematica can do it analytically.
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| Oct 27 at 16:18 | comment | added | azerbajdzan |
Assumptions -> x > t > 0 makes no logical sense, it should be Assumptions -> x > 0.
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| Oct 27 at 16:13 | history | answered | Michael E2 | CC BY-SA 4.0 |