Hello!

I am working with the Maple 18.02 version. I just want want to perform a basic polynomial expansion using the command "expand" and it does not respond as it should according to what Maple Programming Help says it would. For example:

Maple Programming Help says:

I get:

.

Also, one sees that this isn't even true, as x(x+2) + 1 = x^2 +2x +1, which is not equal to x^2 + 3x +2.

Moreover, maple tells me it is equal..:

What is going on here? I woul like to get the full expanded form (without factors). Also, this is obviously not true, or maybe Maple means something else by x(x+2) +1...

Thank you!

I have many integrals which I would like to calculate the value. The one in attachment is the simpliest example.

It shows 'too many level of recursion',

I know that it has something to do with the piecewise, however, it shouldn't, right? Any insights?

evalfandintPerformance.mw

evalfandintPerformance.pdf

I have made an animate-plot with trace function enabled and I was wondering if there was something I could do so it would show the value of the variable when trace reached frame x and y and plot it in the plot or maybe somewhere else.

Thanks in advance.

i use optimization package with constraint hello >= 0

Minimize(xx=0, {hello >= 0})

but solution only return the case when hello = 0

how about hello > 0?

i would like to find all possible set of solutions using this constraint

do i need to set upper bound, such as {hello <= 7, hello >=0}

can it return solution when hello = 1.1, 1.2, ...2, 2.1, 2.2, 2.3, ....7

Hi All

I have the following line of code in Maple:

solve([sin(t), 0 < t, t < 6.28], t, allsolutions, explicit)

it produces: "{t = Pi}, {t = 2*Pi}, {t = 3*Pi}, {t = 4*Pi}, {t = 5*Pi}, {t = 6*Pi}, {t = 7*Pi}"

How do I get it to simply produce: "{Pi,2*Pi,2*Pi,3*Pi,4*Pi,5*Pi,6*Pi,7*Pi}

as having the variable listed is redundant and annoying when you want to go on and extract the 3rd solution (number only) form the list.

Thanks in advance.

i am interested to numerically solve the 3 non-linear coupled ODE's in the 3 different intervals of rho(define in attached file) for the different corresponding parameters alpha and beta at i=0..2.

density_interval_solution.mw 

When using maximize on a relatively complicated function (see attached Maple file and PDF), it runs extremely slow. No return after 3 minutes.

My hardward: i7 2.3G, 8G DDR3 MEM, 500G SSD.

Maybe someone is interested to try the Maple code if your workstation is more powerful? :)

MaximizePerformance.mw

MaximizePerformance.pdf

I hope to dynamically generate the function name via for loop, see enclosed Maple file and PDF file.

Any lights are appreciated.

CatOrCombineFunctionName.mw

CatOrCombineFunctionName.pdf

I have a Maple code which generates a matrix, saves it to a .txt file and this is then read in to a C++ program. I have hit a snag with these matrices, in that they are generating absolutely enourmous .txt files. I need to get to a 5000*5000 matrix yet a 200*200 is generating a 100MB file.

The matrix elements contain a lot of algebraic terms which I would like to keep general as these are defined in the C++ code. They also contain hypergeometric functions which in the example below I have left unsimplified (although they are simplified before reaching C++). I have tried various operations/combinations to simplify, but the file sizes still come out very large.

From previous experience expanding the expressions and then simplifying allows Maple to "do more" with it, but it does not seem to work in this instance. I have tried map(options,expr), simplify(expr,options), combine(expr,options), convert (expr,options) etc... The script attached only contains a small example 10*10 matrix on its own without the code which generates it due to the size of the code. What is the best way to simplify these matrices to generate the smallest .txt file?

Large_Matrix.mw

Any help is appreciated.

-Yeti
 

I am looking for a numerical solver for a parabolic PDE (up to 2nd order derivatives but no mixed ones) on the spatio-temporal domain [X x Y x T], either as an external package or as MAPLE code.  

I have coded the method of lines on the domain [X x T] and indeed also used pdsolve as a check for that case. However, pdsolve (numerical) cannot solve the PDEs on the domain [X x Y x T].  The run times and memory requirements for the latter case would of course be significantly greater.  

I am about to code up the method of lines (in MAPLE) on the domain [X x Y x T], but am wondering whether there exist external FORTRAN or C code packages that would be faster if called up in MAPLE and whose results would then be post-pocessed in MAPLE.

Does anyone have any suggestions?

MRB

Hello,

when trying to solve my equation I always get this error-message:

Error, (in DEtools/convertsys) invalid input: degree expects 1 or 2 arguments, but received 3

To solve, I use this one:

Anfangsbed := phi(0) = 0,  D(phi)(0) = 10;

Einst :=             range = 0..10,            #Integrationsgrenzen
                     relerr = 1e-3,            #Toleranz zur Bestimmung der Integrationsschrittweite
                     optimize = true,          #Optimierung der DGL
                     maxfun = 0,               #Anzahl der Integrationsschritte -- 0 = keine Obergrenze
                     output = operator,        #Lösungsfunktionausgabe: damit Definition als Funktion möglich 
                     stiff = true:

Lösung_Bewgl := dsolve({Bewegungsgl_mit_Para, Anfangsbed}, numeric, Einst);

The equation to solve is this one: http://imgur.com/a/SFxI8

What am I doing wrong?

Edit:

This is the worksheet, problem is the last point.

WS.mw

hello,

I am trying to solve a set of equations using solve but it didn't get me any answer !

> eq1 := x[1]-x[2] = 0;
> eq2 := -x[1]+2*x[2]-x[3] = 0;
> eq3 := -x[2]+2*x[3]-x[4] = 0;
> eq4 := -x[3]+x[4]-t = 0;
> solve({eq1, eq2, eq3, eq4}, {x[1], x[2], x[3], x[4]});

there is no error massage or anything.

any help?

thank you,

Mahdi

Hi,

Please help me to solve numerically and visualise the following time-delayed integro-differential equation (see also the file attached)

diff(x(t), t$2) = .8/(x(t)^3*exp((2*0.1e-1)*(int(1/x(t), t = 0 .. t-tau))))-1/x(t)^2 , 

with the initial conditions x(0) = 1, (D(x))(0) = 0, and tau=0.1 (variable parameter).

The expected solution is an oscillatory function.

Thanks for your time and advice!

IDE.mw

hi--how i can solve following equation?

thanks

Eq.mw


Maple Worksheet - Error

Failed to load the worksheet /maplenet/convert/Eq.mw .
 

Download Eq.mw

I've implemented the optimal taxation model proposed in this paper using Maple.

But it never stops running and get stuck in the last line for integral computation. Any idea of what's wrong with that?

This is the last line:

Here is the full code.