[Numpy-discussion] Remove duplicate columns

T J tjhnson at gmail.com
Thu May 6 13:25:38 EDT 2010


Hi,

Is there a way to sort the columns in an array?  I need to sort it so
that I can easily go through and keep only the unique columns.
ndarray.sort(axis=1) doesn't do what I want as it destroys the
relative ordering between the various columns. For example, I would
like:

[[2,1,3],
 [3,5,1],
 [0,3,1]]

to go to:

[[1,2,3],
 [5,3,1],
 [3,0,1]]

(swap the first and second columns).  So I want to treat the columns
as objects and sort them.  I can do this if I convert to a python
list, but I was hoping to avoid doing that because I ultimately need
to do element-wise bitwise operations.

Thanks!



More information about the NumPy-Discussion mailing list