inconsistent row <-> column sub-vector behavior

[Sergei Steshenko]

Hello All,

here is a small session:

"
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octave:1> vector_length = 4
vector_length =  4
octave:2> column_vector = zeros(vector_length, 1)
column_vector =

   0
   0
   0
   0

octave:3> row_vector = ones(1, vector_length)
row_vector =

   1   1   1   1

octave:4> column_vector(2:vector_length) = row_vector(2:vector_length)
column_vector =

   0
   1
   1
   1

octave:5> column_vector(2:vector_length) += row_vector(2:vector_length)
error: operator +: nonconformant arguments (op1 is 3x1, op2 is 1x3)
error: assignment failed, or no method for `matrix += matrix'
error: evaluating assignment expression near line 5, column 32
octave:5>                   
".

I think that 'octave' behavior is counterintuitive and inconsistent - 
either it should allow both

column_vector(2:vector_length) = row_vector(2:vector_length)
column_vector(2:vector_length) += row_vector(2:vector_length)

or it should disallow both.

Or is it for compatibility with Matlab ? I do not have Matlab, so I can't
check.

Thanks,
  Sergei.