Re: Points sampled by FindMinimum
- To: mathgroup at smc.vnet.net
- Subject: [mg71145] Re: Points sampled by FindMinimum
- From: Bill Rowe <readnewsciv at sbcglobal.net>
- Date: Thu, 9 Nov 2006 03:38:16 -0500 (EST)
On 11/8/06 at 6:06 AM, andrew.j.moylan at gmail.com (Andrew Moylan)
wrote:
>Please consider the following code, which asks FindMinimum to
>minimise a simple parabolic function while tracking at which which
>points FindMinimum evaluates the function:
>func[x_?NumericQ] := (Print[x]; 1 + (x - 1)^2) FindMinimum[func[x],
>{x, 0.1}]
>The output is:
>0.1 0.1 0.1 0.6 0.6 0.6 1. 1. 1. 1. 1. 1.
>But I would have expected output more like:
>0.1 0.6 1. 1.
>Can anyone explain why FindMinimum evaluates func three times at
>each test point, instead of once?
I rather doubt FindMinimum is evaluating the function three
times at each point. I am reasonably certain the difference
between sampled points is simply fairly small and the Print
statement doesn't show enough digits to make it apparent there
is a difference.
That is
In[4]:=
.1000001
Out[4]=
0.1
In[5]:=
.1000002
Out[5]=
0.1
--
To reply via email subtract one hundred and four