I need some help...i need a solver using the Runge-Kutta method adaptive size control, to solve a sytem of 5 diff eq's, all of them are interlinked...

And 

Say that dsolve numeric produces a results, called Solution, Now ex  solution(0)=1, and in general solution(t) can be evaluated, now, i want to use this, in E(t)=2*solution(t), in a plot, thus...

plot(E(t),t=0..100,....), but returns the error....

I have a set of test equations. I am substituting the coefficients of the variables A₁ ..A₄ and the constants in the equations. Most of this I have made work fine. There are 2 coefficients I cand make be substituted. In eq₁ k*d the coefficient of A₃ and eq₅ 3.1d² also the coeff of A₃ .Have tried subs and algsubs but can't make it work. The reason I want to do this is in reality I have 15 equations...

How do I prevent that maple scrolls through the worksheet and stops at the bottom when I want to execute the  whole worksheet. If i want to execute the whole worksheet I just want to stay at the same place in the worksheet and I also don't want to expand previousily closed sections. I use document mode. Thanks in advance

aim: To solve the van der pool DE  assuming pertubation expansion

how can i solve pdes of the following form in maple

[tex] tc(t,x)\frac{\partial a(t,x)}{\partial t} - ta(t,x)\frac{\partial c(t,x)}{\partial t} = a(t,x)c(t,x) + t(a(t,x))^2 and be able to find both functions a(t,x) and b(t,x)

I installed Maple 16 on Windows 7, 64 bit, french edition, last week. Everything works fine, except that suddenly the Maple 16 icon has been replaced by the anonymous exec file on windows. Tried to restart, but the icon is gone...

Does anyone else get this problem ?

Hello.  The ‘optimization’ flag for the fortran codegen or CodeGeneration only will operate on a single array.   It would be very very helpful to me if I could put multiple arrays (all of them having common variables) as input that the codgen and CodeGeneration can automate all at once (im mostly interested in the fortran and matlab codes).  What I do now as a work around is manually put all the multiple arrays into one giant array, then run code...

Hi guys, 

I want to know how to write 2 procedures in order to  construct 2 different complex mappings with polynomials of degree 4 and 5 and tell what the pictures really mean.

Can anyone suggest me or give me hints on how to do this? 

One way I know is to construct meldelbrot as follow: 

mandelbrot:=proc(x,y)

localz,ct,xn,xnold,yn,iter:

Iter:=25:Digits:=10:xn:=x:yn:=y:

for ct from 1 to iter while xn^2+yn^2

I've written some Matlab codes as mfiles; now how could I import them into Maple? (I didn't understand what Maple help says!)

i 

Hi,

I am using Maple 13 under Windows 7. I have been using Maple for quite a while now, and all of a sudden Maple has decided to start playing funny games.

Whenever I go into the Maple Portal and click on one of the hyperlinks, the Maple session locks up. The first time this had happened, I had been in the Maple Portal for half an hour.

It doesnt respond to any clicks, including trying to close the Maple window. The only way to close it at this point is to crash it via the Task Manager....

Up until now, I have been using lists instead of sets in solve() in order to ensure the first equation is solved for the first variable, the second for the second, etc.  However, I have run into a case for which using an equation list and a variable list does not work, but the equation list alone is fine, and sets of both are fine, etc.  I would be grateful if somebody can explain why the first statement below does not produce a solution.

> soln := solve([foc1 = 0, foc2 = 0, foc3 = 0...

old version define use
'homalg/default':=RPI;

in maple 15
libname := "D:/homoalg/10_homalg.lib",libname:
with(homalg):

> define(homalg, RPI, 'default');
Error, (in define) homalg is assigned
> hom2 := Hom(L, K, var);
Error, (in homalg/tablename) Since homalg/default is not defined, the last argument must be a table containing the (minimum) homalg conversions or an unassigned symbol pointing to such a table!
> define(homalg, 'RPI', 'default');

I want to solve numerically the nonlinear problem 

a*(diff(y(x), x, x))+2*(diff(y(x), x))+exp(y(x)) = 0, y(0) = 0, y(1) = 0

by defining my own method defined as 

y_n+1=y_n+2*h*(-2*y_n+2*ln(2/(1+x))-(1/2)*a)^2/(a*(-4*y_n+4*ln(2/(1+x))-a-h*(4*y_n-4*ln(2/(1+x))+a+x+1)/a))

where h is the step-size. Please help me by letting me know how can I do this using Maple 11.

Hi evryone.

Does anyone have experience on what is the best format to export an entire worksheet (code and graphics) out of Maple. I tried all different formats but none comes even close to being publication quality.

thanks a lot

Hi all,

I have an array [1..2503] y-axis for different values,  x-axis [0..180], 

when I plot these two arrays its not possible.   but if I change x-axis [1..2503] then plot is ok... I want to plot x-axis [0..180] and y-axis [1..2503]

Regards

A.Q   Soton