possible Matrix constructor bug
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Adrian Seyboldt
Mar 14, 2012, 7:26:53 AM3/14/12
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Hello,
When creating a Matrix from another one, no new object is created
m1 = Matrix(2, 2, range(4))
m2 = Matrix(m1)
m1 is m2
returns True, so changing m1 will also change m2. I know I can use m1.clone(), but
since SomeClass() usually creates a new object, this took me rather by surprise.
Is this intended behavior?
Adrian Seyboldt
When creating a Matrix from another one, no new object is created
m1 = Matrix(2, 2, range(4))
m2 = Matrix(m1)
m1 is m2
returns True, so changing m1 will also change m2. I know I can use m1.clone(), but
since SomeClass() usually creates a new object, this took me rather by surprise.
Is this intended behavior?
Adrian Seyboldt
Matthew Rocklin
Mar 14, 2012, 11:53:35 AM3/14/12
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Hrm, yes, this should probably change.
Having things the way they are now accelerates a few internal functions. This acceleration probably isn't worthwhile though given the confusion you bring up. I'll send in a PR with this change in a bit.
In general the internals of Matrices were changed around a bit in a recent commit. Bug reports like this are very useful.
-Matthew
Adrian Seyboldt
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Matthew Rocklin
Mar 14, 2012, 12:47:46 PM3/14/12
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