Thread: [matplotlib-devel] changes to collections, etc.

I have commited a set of changes to _transforms, collections, quiver, 
contour, and numerix as part of a move toward taking advantage of the 
efficiency of numerix arrays in place of sequences of tuples.  The 
changes are outlined very briefly in CHANGELOG and API_CHANGES.

Changes in clabel are hacks, and may make it less efficient rather than 
more, but I expect this to be temporary; I needed to simply make it work 
with the other changes.

Where breakage will occur is any place in user code that expects the 
collection segments or vertices to be lists of tuples and tries to 
append to the list, for example.  I don't know of any way to make the 
move towards use of arrays without this problem cropping up; I hope it 
is considered tolerable.

Eric

>>>>> "Eric" == Eric Firing <ef...@ha...> writes:

    Eric> Where breakage will occur is any place in user code that
    Eric> expects the collection segments or vertices to be lists of
    Eric> tuples and tries to append to the list, for example.  I
    Eric> don't know of any way to make the move towards use of arrays
    Eric> without this problem cropping up; I hope it is considered
    Eric> tolerable.

If I'm understanding you correctly:  Users who create the collection
themselves with the list of xy tuples approach can still modify their
lists, eg with append, and not have breakage (I actually use this
feature).  But users who are getting collections back from code like
contour will get the non-modifiable array version.

John Hunter wrote:
>>>>>>"Eric" == Eric Firing <ef...@ha...> writes:
> 
> 
>     Eric> Where breakage will occur is any place in user code that
>     Eric> expects the collection segments or vertices to be lists of
>     Eric> tuples and tries to append to the list, for example.  I
>     Eric> don't know of any way to make the move towards use of arrays
>     Eric> without this problem cropping up; I hope it is considered
>     Eric> tolerable.
> 
> If I'm understanding you correctly:  Users who create the collection
> themselves with the list of xy tuples approach can still modify their
> lists, eg with append, and not have breakage (I actually use this
> feature).  But users who are getting collections back from code like
> contour will get the non-modifiable array version.
> 
> 

John,

Yes, that is the way it is supposed to work.  The collection stores and 
  uses whichever form it is given.  This can work because the XY array 
is very similar to the [(x,y), (x,y)...] form; both are single objects, 
and they behave the same when one says, "for xy in XY:", or if one calls 
the array constructor with either as an argument.

Eric