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multi-threading -> cholesky factorization error, rospy

asked 2014-08-13 10:14:06 -0500

holmes.kirby
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Hello All,

I have two callbacks within a class that share the same data in python. Is it possible that these callbacks are altering the data at the same time?

I am getting an error while trying to take the cholesky of a covariance matrix.

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answered 2014-08-13 10:52:30 -0500

Chrissi

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That is perfectly possible. Both run in different threads and might therefore write to the same variable while you're reading it. It must not even be both at the same time but if you are reading it outside the callback then the callback might write to it while reading.

Have a look at this to see how thread safety and locks work in python.

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This looks perfect! Hopefully this turns out to be the problem.

thanks

holmes.kirby ( 2014-08-13 11:23:49 -0500 )edit

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Asked: 2014-08-13 10:14:06 -0500

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Last updated: Aug 13 '14

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