Copy constructor

[nils-werner]

This is inspired by NumPy's behaviour, where people tend to do numpy.array(a) on any iterable a, including ndarrays, just to make sure it is an ndarray.

Do you think something like this would make sense? Would save us having to do type checks in places where we just want to make sure it is a COO instance.

[hameerabbasi]

flake8 is crapping out here. You can have a maximum of one continuous blank line inside of a function.

[hameerabbasi]

I would leave these as-is, or maybe change them to arrays = [x if isinstance(x, COO) else COO(x) for x in arrays]. Generally, we want to avoid making copies where possible.

I realize what you are doing is a shallow copy, not a deep one, but in the future, if we allow manipulation of arrays (if we make the COO type mutable), we might need to change this to a deep copy, and that might be expensive.

[hameerabbasi]

Some minor comments.

[hameerabbasi]

Actually, it'd be nice to have a test for equality. Something like generating a random matrix and then COO(x) , asserting they're not the same object, and an assert_eq.

[mrocklin]

Do we also want to ensure that the data and coords arrays are not the same?

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On Tue, Jan 2, 2018 at 3:23 AM, Hameer Abbasi ***@***.***> wrote: Actually, it'd be nice to have a test for equality. Something like generating a random matrix and then COO(x), asserting they're not the same object, and an assert_eq. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <https://github.com/mrocklin/sparse/pull/55#issuecomment-354747301>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AASszJxuWNBh7wzpqOYMGeCXHrch2Aifks5tGhHJgaJpZM4RPjj6> .

[hameerabbasi]

I don't know the convention in Python here. I know Numpy makes a deep copy but we might get away with a shallow one since we're not mutating the original data and coords in any way. I'm good with this until it raises issues (which I suspect won't be for a long time since COO is immutable).

[mrocklin]

OK, sounds good to me

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On Tue, Jan 2, 2018 at 9:23 AM, Hameer Abbasi ***@***.***> wrote: I don't know the convention in Python here. I know Numpy makes a deep copy but we might get away with a shallow one since we're not mutating the original data and coords in any way. I'm good with this until it raises issues (which I suspect won't be for a long time since COO is immutable). — You are receiving this because you commented. Reply to this email directly, view it on GitHub <https://github.com/mrocklin/sparse/pull/55#issuecomment-354821260>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AASszHd90nAVvLeyfgRySctu0EbqZl7zks5tGmYtgaJpZM4RPjj6> .