Services & ResourcesWolfram ForumsMathGroup Archive

[Date Index] [Thread Index] [Author Index]

Re: output in NMinimize on each step?

• To: mathgroup at smc.vnet.net
• Subject: [mg46458] Re: output in NMinimize on each step?
• From: scohen at cable.net.co (Sebastian Cohen S)
• Date: Thu, 19 Feb 2004 03:02:13 -0500 (EST)
• References: <c0t0fp$2i7$1@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

In the version 5.0 the StepMonitor function works but I tried it on
another problem (with more variables and equations - about 48 & 12
respectively) and it simply returns the solution but with no printed
steps.

Any ideas why this happens?

Thanks,

Sebastian Cohen S

Omega Consulting <info at omegaconsultinggroup.com> wrote in message news:<c0t0fp$2i7$1 at smc.vnet.net>...
> At 06:16 AM 2/12/2004, mfific wrote:
> >I would appreciate suggestion how to get an output on each step during
> >minimization process in NMinimize.
> >
> >I am surprised  this has not been included as an option in Nminimize,
> >because it is very useful to see what is Mathematica doing.
> >
> >The solution for getting an output could  be found for FindMinimum, but
> >somehow I cannot use that in NMinimize.
> >An example would be very helpful.
> >
> >thanks,
> >
> >Mario Fific
> 
> In version 5, there's the StepMonitor option.
> 
> In[1]:= Options[NMinimize]
> Out[1]=
> {AccuracyGoal -> Automatic, EvaluationMonitor -> None, MaxIterations -> 100,
>    Method -> Automatic, PrecisionGoal -> Automatic, StepMonitor -> None,
>    WorkingPrecision -> MachinePrecision}
> 
> In[2]:= ?StepMonitor
> StepMonitor is an option for iterative numerical computation \
> functions that gives an expression to evaluate whenever a step is taken by \
> the numerical method used.
> 
> In[3]:= NMinimize[{x^2 + (y - 0.5)^2, y >= 0 && y >= x + 1},
>    {x, y}, StepMonitor :> Print[{x, y}]]
> 
> --------------------------------------------------------------
> Omega Consulting
> "The final answer to your Mathematica needs"
> http://omegaconsultinggroup.com

• Follow-Ups:
  • Re: Re: output in NMinimize on each step?
    • From: Daniel Lichtblau <danl@wolfram.com>