Math Forum / Math Software / Mathematica / July 2008

Hi, I was wondering if someone might be able to help me with some  
NMaximize issues? Thanks, Stuart
1. Is there any limit to the number of variables in NMaximise. Is it  
possible/sensible to run a model with about 1,300 variables?

Consider the following:
z := {L == x y, y == x, x == y}
Solve[z, {L}] --->  {{L->y^2}}
no surprises. now,

Given this:
K = (1+vy) (zx+wx)  + vx (zy+wy);
Expand[K^2]
Is it possible to remove automatically the 3rd and 4th orders from the

Is there a straight-forward way to write a function that takes a list
of symbols that are bound in the calling environment and produce a
list such as is produced by Solve, like {var1->val1, var2->val2,...}?
Currently, I'm using an expression (not a function) like {Hold[var1]-

I'm trying to do an autocorrelation analysis on an artificially generated
neuronal spike train, but BinCounts is behaving strangely.
I first generate a list of spike times for an oscillator with a mean
frequency of 1 Hz, plus some gaussian jitter:

Newbie question.
SOLVE documentation indicates I have to include assumptions to solve this (I
thought) simple problem:
<snip>

I met a problem, in ABC.nb , I need to run XYZ.nb, is there any
function to execute the XYZ.nb in ABC.nb?
cheers,
leo

In[]:= f'[x] =!= f[x]' && f''[x] === f'[x]'
Out[]= True
Can anyone explain this?
-Ben

With the code below, plot1 gives a line from -a to 0 (in the complex
plane). plot2 should give the the symmetric of plot1 with respect to the
unit circle, i.e., a line from -1/Conjugate[a] to infinity (same slope as
line from -a to 0). I cannot get plot2 to give the correct line. ...

Basically, I would like to run the following command from Mathematica:
idl /users/burkart/idlpro/autoexportdata.bat
If I type this command into a terminal (I'm running Mac OSX Leopard), it works perfectly well. However, if I try the same thing using Mathematica's Run[] command, it ...

Hello Mathematica Friends,
When I used NDSolve[] to a set of equations (one equation used an interpolating function), I got an error message saying,
NDSolve::dsfun: {InterpolatingFunction[{{0.,1.}},<<3>>,{Automatic}][t]} cannot be used as a function. >>
Error message details show ...

I've got a list of data that I'd like to Export into Excel. The twist
is, I'd like to export each element of the list into a separate
worksheet within the same Excel Workbook. Can this be done in Mathematica v6?
Thanks,

I would like to manipulate a plot created from three different parametric
plots. I display the plot with Show[plot1,plot2,plot3] (see code below).
If I try this in Manipulate, the plots are displayed next to each other. I
need them in a single plot. I cannot combine them in a ...

How does one unprotect symbol Pi and the Greek lower case letter pi
(&#960;)?  Unprotect[Pi] doesn't seem to do the job.
Pi // N
3.14159

I tried to solve the following equation with mathematica 6.03
Solve[{Abs[X+Y I]==5,X==3},{X,Y}]
and got the answer
{{X -> 3, Y -> -2 I}, {X -> 3, Y -> 8 I}}