> On 31 Jul 2017, at 04:01, Thomas D. Dean <address@hidden> wrote:
>
> On 07/30/2017 05:21 PM, Tatsuro MATSUOKA wrote:
>
> On 4.3.0+, ( local build, two weeks ago)
>
> octave:321> fvdb = @(vt,vy) [vy(2); (1 - vy(1)^2) * vy(2) - vy(1)];
> octave:322> vopt = odeset ("RelTol", 1e-3, "AbsTol", 1e-3, "NormControl", "on", "OutputFcn", @odeplot);
>
> octave:323> ode45 (fvdb, [0 20], [2 0], vopt);
> warning: Option "InitialStep" not set, new value 2.000000 is used
> warning: called from
> ode45 at line 182 column 5
> warning: Option "MaxStep" not set, new value 2.000000 is used
> warning: called from
> ode45 at line 190 column 5
> octave:324> line 104: warning: Cannot toggle log scale for volatile data
>
> But, I get a plot...
>
> Tom Dean
With mercurial revision 90689bdbe048 (pulled and built on friday)
>> fvdb = @(vt,vy) [vy(2); (1 - vy(1)^2) * vy(2) - vy(1)];
>> vopt = odeset ("RelTol", 1e-3, "AbsTol", 1e-3, "NormControl", "on", "OutputFcn", @odeplot);
>> ode45 (fvdb, [0 20], [2 0], vopt);
I get no warning and the attached plot (is that what you expect?).
As far as I remember, the warnings for using the default values of ode options were removed
before the release of 4.2 including ode45. Maybe you have an odepkg installation that shadows
the core function?
Anyway all those warnings seem harmless although annoying.
c.
odepkg.pdf