[Octave-bug-tracker] [bug #50924] Different result between range operation and vector operation

[John W. Eaton]

Update of bug #50924 (project octave):

                Priority:              5 - Normal => 3 - Low                
              Item Group:        Incorrect Result => Inaccurate Result      
                  Status:                    None => Confirmed              

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Follow-up Comment #1:

The difference happens because multiplying a range object by a scalar changes
the base, limit, and increment values, and then the elements (when needed) are
computed using those new values.  It's as if you wrote


step:step:(n*step)


instead.  In the vector case, the values are computed by multiplying STEP by
each integer in the range 1:n.

I agree that they should return the same result if possible.  OTOH, the range
operator in Octave is a space optimization and the difference is less than
eps.

You can completely disable Octave's special range type using


disable_range (true);


Maybe we should also have another setting that forces a range to vector
conversion whenever an operation other than indexing is performed on a range
object, and that operation would result in the endpoints or step no longer
being integers?

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