Basic plotting of an evaluated function
- To: mathgroup at smc.vnet.net
 - Subject: [mg86881] Basic plotting of an evaluated function
 - From: "lederer at ssb.rochester.edu" <lederer at ssb.rochester.edu>
 - Date: Tue, 25 Mar 2008 01:15:15 -0500 (EST)
 
I am trying to do something basic--but I cannot figure it out
I have some function in two varaibles
f[x_,y_]= some arbitrary polynomial
Now I want to minimize the function with respect to y over some
compact interval with fixed x
NMinimize[{f[x,y],y=995,y=989},y]
I want to plot the y's versus the x's.
I have tried many things like defining
s[x_]=Part[NMinimize[{f[x,y],y=995,y=989},y],2]
Plot[s[x],{x,-14, 46}]
or variations
Plot[tt/.s[x],{x,-14, 46}].
Many error messages or nothing at all results.........
I am sure this is easy, and someone can suggest how to do this.
However, one more thing would be greatly helpful (give a man a decent
and readable Mathematica manual and he can feed himself...)
I am baffled by what Mathematica wants when it comes to using a single
part of a list and changing it to a scalar.  Suppose as above q is a
vector with a rule assigning a value to some variable x  that is x-
>some number, and this assignment is in the third position of the list
What is going on with  q/.d[[3]] for example: Is q now a scalar?  If
not why  not?
Thanks for you help,
Phil Lederer