How can I control FindMinimum's behavior?

*To*: mathgroup at smc.vnet.net*Subject*: [mg19037] How can I control FindMinimum's behavior?*From*: Rajdeep Kalgutkar <rajdeep at chem.nwu.edu>*Date*: Tue, 3 Aug 1999 13:45:06 -0400*Organization*: Northwestern University*Sender*: owner-wri-mathgroup at wolfram.com

Hi Mathgroupers! I have been using FindMinimum for a multidimensional minimization problem. I find that when Method->Automatic is used, my input parameters values are passed on to my target function immediately, but when I use Method->QuasiNewton, FindMinimum insists on symbolic input during the first minimization cycle. This happens even though I specify 2 input values. My target function does not have symbolic derivatives and therefore it the minimization procedure crashes when using the QuasiNewton method. Is there anyway to prevent FindMinimum from insisting on symbolic input initially? I am using Mathematica For Students 3.01, in case that is relevant. thanks for helping out, rajdeep eg: In[1]:=func[x_]:=Module[{w}, w=Sin[x]^2+0.2*x; Print[w," ",x]; w ] In[2]:=FindMinimum[func[x],{x,{0.,1}},Method->Automatic] 0. 0. 0.00725537 0.0313609 -0.00350081 -0.0193821 -0.0100333 -0.100024 -0.0100336 -0.100373 -0.00640346 -0.161842 -0.00906033 -0.0692214 -0.00951906 -0.123636 -0.0100333 -0.100024 -0.0100337 -0.100727 -0.0100337 -0.10068 Out[2]={-0.0100337,{x->-0.10068}} In[3]:=FindMinimum[func[x],{x,{0.,1}},Method->QuasiNewton] 0.2 x + Sin[x]^2 x FindMinimum::"fmwar": "When Method -> Newton or QuasiNewton only the first starting value in each dimension will be used." 0. 0. -0.000530497 -0.2 -0.000530497 -0.2 -0.0100297 -0.102717 -0.0100297 -0.102717 -0.0100337 -0.100623 -0.0100337 -0.100623 -0.0100337 -0.100679 -0.0100337 -0.100679 -0.0100337 -0.100679 -0.0100337 -0.100679 Out[3]={-0.0100337,{x->-0.100679}}