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Bug 890 - More robust detection of identical source/destination in PermutationMatrix products
More robust detection of identical source/destination in PermutationMatrix pr...
Product: Eigen
Classification: Unclassified
Component: LU
All All
: Normal Wrong Result
Assigned To: Nobody
Depends on:
Blocks: 3.3
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Reported: 2014-10-09 22:14 UTC by ettersi
Modified: 2015-06-10 08:10 UTC (History)
3 users (show)

Small example program showing the problem (805 bytes, text/x-c++src)
2014-10-09 22:14 UTC, ettersi
no flags Details

Description ettersi 2014-10-09 22:14:40 UTC
Created attachment 498 [details]
Small example program showing the problem

If all three "arguments" (matrix, rhs and output object) to partialPivLU are Maps, the output object is not written. 

I attached you a small example program showing the problem. It is slightly more complicated than a minimal example, but this is the exact situation I would like to work.
Comment 1 Gael Guennebaud 2014-10-10 16:24:43 UTC
It works fine with the devel branch. I'll investigate what goes wrong with the 3.2 branch.
Comment 2 Gael Guennebaud 2014-10-10 16:47:43 UTC
Partial fix:
Changeset:   ce8b4f787c0a
Branch:      3.2
User:        ggael
Date:        2014-10-10 14:42:32+00:00
Summary:     Bug 890: extract_data might returns 0x0 thus breaking aliasing detection

however, we still need a more robust mechanism to detect the input/output are same in both 3.2 and devel branch.
Comment 3 Gael Guennebaud 2015-06-10 08:10:19 UTC
The following changesets should be good enough to close this entry.
Summary:     Add regression test for bug 890
Summary:     Bug 890, add a more general routine to check that two dense object reference to the same data

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