Christopher Barker wrote:
Thanks all,
Robert Kern wrote:
Look at vstack() (and also its friends hstack(), dstack() and column_stack() for completeness).
I like this, but need to keep Numeric/numarray compatibility for the moment -- I think, I've just sent out a query to my users.
Tim Hochberg wrote:
If you are using real arrays, use newaxis:
>>> a array([0, 1, 2]) >>> b array([3, 4, 5]) >>> concatenate([a[newaxis], b[newaxis]], 0) array([[0, 1, 2], [3, 4, 5]])
I like this, but again, not in Numeric -- I really need to dump that as soon as I can!
In Numeric, you can use NewAxis instead for the same effect.
hate newaxis, wrap the arrays in [] to give them an extra dimension. This tends to look nicer, but I suspect has poorer performance than above (haven't timed it though):
>>> concatenate([[a], [b]], 0) array([[0, 1, 2], [3, 4, 5]])
Lovely. much cleaner.
By they way, wouldn't wrapping in a tuple, be slightly better, performance-wise (I know, probably negligible, but I always feel that I should use a tuple when I don't need mutability)
I doubt it would make a signifigant difference and the square brackets are much easier to read IMO. Your mileage may vary. -tim