bugGNU Octave - Bugs: bug #59116, Return value for the String...


bug #59116: Return value for the String property of uicontrol

Submitted by:  Guillaume <gyom>
Submitted on:  Tue 15 Sep 2020 06:51:31 PM UTC  
Category:  Plotting Severity:  2 - Minor
Priority:  3 - Low Item Group:  Matlab Compatibility
Status:  Confirmed Assigned to:  None
Originator Name:  Guillaume Open/Closed:  Open
Release:  dev Operating System:  Any

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Wed 16 Sep 2020 03:25:25 PM UTC, comment #1: 

Marking as confirmed, and changing the severity to Minor.

The first two instances, where Octave returns a string but Matlab returns a char matrix, are the ones to focus on.

The code to start looking through is in graphics.in.h and the class definition for string_array_property.  The class provides an overload for the string_value() function that creates the pipe-delimited list.

  std::string string_value (void) const
    std::string s;

    for (octave_idx_type i = 0; i < str.numel (); i++)
        s += str[i];
        if (i != str.numel () - 1)
          s += separator;

    return s;

There would probably need to be a new conversion function with an output of char matrix rather than std::string.  This conversion function would essentially just call Fchar() on the list of strings.  And then there would be changing the get function for "string" so that it returned a char matrix so it would pick up the new overload.

Rik <rik5>
Project Administrator
Tue 15 Sep 2020 06:51:31 PM UTC, original submission:  

There is a small difference between Matlab and Octave regarding the return value of the String property of a uicontrol widget:

in = { 'a|b|c', ['a';'b';'c'], {'a','b','c'}, ["a","b","c"]};
for i=1:numel(in)
  U = uicontrol ('Style', 'listbox', 'String', in{i});
  get (U, 'String')

Matlab returns:

ans =
  3x1 char array
ans =
  3x1 char array
ans =
  3x1 cell array
ans =
  3x1 cell array

Octave returns 'a|b|c' for the first two and does not yet understand string vectors. Compatibility would be achieved by returning char arrays instead of pipe-separated char vectors.

Guillaume <gyom>


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    Follow 3 latest changes.

    Date Changed by Updated Field Previous Value => Replaced by
    2020-09-16 rik5 Severity3 - Normal => 2 - Minor
        Priority5 - Normal => 3 - Low
        StatusNone => Confirmed

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