[Octave-bug-tracker] [bug #50286] [octave forge] (statistics) fitgmdist: No input check and demo doesn't work

[Nicholas Jankowski]

Update of bug #50286 (project octave):

              Item Group:                    None => Unexpected Error or
Warning
                  Status:                    None => Need Info              
                 Release:                   4.2.0 => dev                    

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Follow-up Comment #2:

just updating this report with the detail about the failing demo

after successfully running fitgmdist, attempting a contour plot first requires
a data reshape, resulting in:


> reshape (GMModel.pdf (bbins), heights)
error: out of memory or dimension too large for Octave's index type


the output from GMModel.pdf(bbins) is 100x1. heights is a 10x10 array (integer
valued doubles) coming from a histogram output. the sum of all the elements in
heights is 200, and every row/column has at least one zero it it, so I'm
really not certain why we're getting the memory/index type error when reshape
should really just be erroring about problematic input for the size vector.

ASSUMING the intent was to reshape it into size(heights), which does work, you
then get a contour plot with two peaks.  unfortunately, the next line:

plot (centers (:, 1), centers (:, 2), "kv", "markersize", 10)

is asking for a variable centers that has never been defined, nad there is no
such prop/method for GMModel.  based on the contour plot, I assume there's
some way to pull out markers for the two peak values to plot, and that was the
intent, but not being familiar with the gmdistribution class, I didn't see any
with a quick scan.  

perhaps if someone who knows the original intent or is familiar with that
class can supply that info, that line can be corrected and the demo will run.


i see @lachlan as the original copyright. adding to cc in case he's still
around and has insight.

it might also be worth checking why the reshape command is producing the
memory/limit error instead of failing an input size check in the current code.


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