Re: deleting column/row from interval Matrice

[Oliver Heimlich]

On 08.11.2016 17:47, karamov wrote:
> hi,
> 
> I'm using octave for 1 week now, using the pkg intervals I'm facing the
> following issue while trying to delete a column from a matrice of intervals:
> <http://octave.1599824.n4.nabble.com/file/n4680529/Capture_d%E2%80%99e%CC%81cran_2016-11-08_a%CC%80_17.png>
>  
> 
> I don't want to just replace the row with two empty intervals, because the
> size of my matrice will grow fastly.

Hi,

>> g(:, 1) = []

gives a dimension mismatch error in your example.  The method
@infsup/subsasgn tries to call the builtin subsasgn function, which
behaves in a strange way:

error: subsasgn: A(I,J,...) = X: dimensions mismatch
error: called from
    subsasgn at line 54 column 3
error: assignment failed, or no method for 'class = null_matrix'

It looks like an Octave error and I will look further into it.



>> g(:, 1) = infsup ()

Here “infsup ()” returns a scalar empty interval (not an empty matrix)
and subscripted assignment works as expected by setting all entries of
the first column to empty intervals.



>> g = g(:, 2:end)

The other proposal from James Sherman Jr. doesn't work on my system,
there seems to be something wrong with the end keyword… I will look into
it as well.  In the meantime you might try:

>> g = g(:, 2:3)



Best regards
Oliver