[Octave-bug-tracker] [bug #59659] Unlimited memory usage through octave gui running ode(15s) solver

[anonymous]

Follow-up Comment #3, bug #59659 (project octave):

I've take a much more deeper look in the model helping me in localizing the
error/problem.
I don't think anymore, that the ode solver is the problem -> maybe you can
rename the bug for clarification, it is the used root finding and/or
redefintion of a function handle in every solver time step. Please see that
attached example.

It's really curios...using a predefined/static function handle, the is no
exzessive memory rise during the loop, also with fzero.

Only redefining the function handle inside the loop without any call to fzero
increases the memory over the loop count. The same arise with the subsequent
call of fzero.


#
for k = 1:1e4
  disp(k)
  # version 1: no memory rise
end
#
fx = @(x) x.^3 + x^2 - 1;
for k = 1:1e4
  disp(k)
  # version 2: no memory rise
  options = optimset('TolX',1e-12);
  fzero(fx,[0,5],options);
end
#
for k = 1:1e4
  disp(k)
  # version 3: memory rise
  fx = @(x) x.^3 + x^2 - 1 - k/1e4;
end
#
for k = 1:1e4
  disp(k)
  # version 4: memory rise
  options = optimset('TolX',1e-12);
  fx = @(x) x.^3 + x^2 - 1 - k/1e4;
  fzero(fx,[0,5],options);
end
#


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