[Octave-bug-tracker] [bug #49364] odeset does not implement non-exact match to property name.

[Rik]

URL:
  <http://savannah.gnu.org/bugs/?49364>

                 Summary: odeset does not implement non-exact match to
property name.
                 Project: GNU Octave
            Submitted by: rik5
            Submitted on: Sun 16 Oct 2016 10:23:33 AM PDT
                Category: Octave Function
                Severity: 3 - Normal
                Priority: 5 - Normal
              Item Group: Matlab Compatibility
                  Status: Confirmed
             Assigned to: None
         Originator Name: 
        Originator Email: 
             Open/Closed: Open
         Discussion Lock: Any
                 Release: 4.2.0-rc2
        Operating System: Any

    _______________________________________________________

Details:

In Matlab, odeset will match a partial property name to the exact property
name.  Octave does not do this.  Instead, it creates a new property under the
abbreviated name.

This is a problem.  Code on Matlab which makes use of this feature does not
generate any warning, therefore, there is no indication that the option should
be written more specifically.  When this code is ported to Octave, it will
run, but differentent results will be obtained because some options have not
been set identically.  As an example,


odeset ('Rel', 1e-12)


will set RelTol to a very strict 1e-12 in Matlab, but leave it at the default
value in Octave.

Test code:


% Should ignore case and set RelTol, is list of properties still alphabetic?
x = odeset ('reltol', 1e-1)
% Does Matlab error or warn when option value is incorrect?
y = odeset ('RelTal', 1e-2)
% Does Matlab auto-complete to nearest available property as for graphics?
z = odeset ('Rel', 1e-3)
% Can arbitrary properties be added?
w = odeset ('MyCustomProperty', 1)


Results:


These are the outputs on r2016a:

x = odeset ('reltol', 1e-1)

x =

               AbsTol: []
                  BDF: []
               Events: []
          InitialStep: []
             Jacobian: []
            JConstant: []
             JPattern: []
                 Mass: []
         MassSingular: []
             MaxOrder: []
              MaxStep: []
          NonNegative: []
          NormControl: []
            OutputFcn: []
            OutputSel: []
               Refine: []
               RelTol: 0.1000
                Stats: []
           Vectorized: []
     MStateDependence: []
            MvPattern: []
         InitialSlope: []

___________________

y = odeset ('RelTal', 1e-2)
Error using odeset (line 225)
Unrecognized property name 'RelTal'.

__________________

z = odeset ('Rel', 1e-3)

z =

               AbsTol: []
                  BDF: []
               Events: []
          InitialStep: []
             Jacobian: []
            JConstant: []
             JPattern: []
                 Mass: []
         MassSingular: []
             MaxOrder: []
              MaxStep: []
          NonNegative: []
          NormControl: []
            OutputFcn: []
            OutputSel: []
               Refine: []
               RelTol: 1.0000e-03
                Stats: []
           Vectorized: []
     MStateDependence: []
            MvPattern: []
         InitialSlope: []

_______________________

w = odeset ('MyCustomProperty', 1)
Error using odeset (line 225)
Unrecognized property name 'MyCustomProperty'.







    _______________________________________________________

Reply to this item at:

  <http://savannah.gnu.org/bugs/?49364>

_______________________________________________
  Message sent via/by Savannah
  http://savannah.gnu.org/