- status: open --> pending
integrate(t^(-1.2),t);
gives
5.000000000000001
- -----------------
0.2
t
must be
5
- -----------------
0.2
t
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No. Compare with 1/(-1.2+1) -> 5.000000000000001
If you wanted the exact number -6/5, you should have said so instead of using the floating point number 1.2.
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But
integrate(t^(-1.2),t,t1,t2); ("positive" for all questions)
gives true
5 5
----- - -----
1/5 1/5
t1 t2
This is a bug or feature?
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Good point. I would consider this a bug in the definite integration routines.
At the very least, it should warn about converting a float to a rational.
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I ran this again, and I actually get warnings about converting a float to a rational.
I think this is acceptable. I think it would be better if it didn't do this conversion, though.
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no, the result is correct because
(%i27) 1/(-1.2+1);
(%o27) - 5.000000000000001
you are using floating point arithmetic and therefore you have rounding errors
actually 0.2 cannot be represented as float without rounding errors (if you are using a binary representation). use exact numbers (e.g t^(-6/5) ) if you want an exact result
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Marking this "Rejected". Agreed w/ comments by nobody dated 2007-01-31 02:17.
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