I wanted to make a 3d plot with lines linking points, but I am struggling with it
(I couldn't find anything in the plot3d documentation, so it might not be supported, which would be odd as its such a normal thing to want to do)

I have tried with no success:

plot3d([1, 2, 3], [4, 5, 6]);
plot3d(Matrix(2, 3, {(1, 1) = 1, (1, 2) = 2, (1, 3) = 3, (2, 1) = 4, (2, 2) = 5, (2, 3) = 6}))

Any thoughts?

hi, i am trying to get a list of equations using the coeff function. I have the following equation:

restart;
Lambda:=-(1/8)*(D[4](a))(x, y, t, u(x, y, t), diff(u(x, y, t), x), diff(u(x, y, t), y), diff(u(x, y, t), t), diff(u(x, y, t), x, x), diff(u(x, y, t), y, x), diff(u(x, y, t), x, t), diff(u(x, y, t), y, t), diff(u(x, y, t), t, t))*(diff(u(x, y, t), x))-(1/8)*(D[6](a))(x, y, t, u(x, y, t), diff(u(x, y, t), x), diff(u(x, y, t), y), diff(u(x, y, t), t), diff(u(x, y, t), x, x), diff(u(x, y, t), y, x), diff(u(x, y, t), x, t), diff(u(x, y, t), y, t), diff(u(x, y, t), t, t))*(diff(u(x, y, t), y, x))-(1/8)*(D[7](a))(x, y, t, u(x, y, t), diff(u(x, y, t), x), diff(u(x, y, t), y), diff(u(x, y, t), t), diff(u(x, y, t), x, x), diff(u(x, y, t), y, x), diff(u(x, y, t), x, t), diff(u(x, y, t), y, t), diff(u(x, y, t), t, t))*(diff(u(x, y, t), x, t))-(1/8)*(D[5](a))(x, y, t, u(x, y, t), diff(u(x, y, t), x), diff(u(x, y, t), y), diff(u(x, y, t), t), diff(u(x, y, t), x, x), diff(u(x, y, t), y, x), diff(u(x, y, t), x, t), diff(u(x, y, t), y, t), diff(u(x, y, t), t, t))*(diff(u(x, y, t), x, x))-(1/8)*(D[12](a))(x, y, t, u(x, y, t), diff(u(x, y, t), x), diff(u(x, y, t), y), diff(u(x, y, t), t), diff(u(x, y, t), x, x), diff(u(x, y, t), y, x), diff(u(x, y, t), x, t), diff(u(x, y, t), y, t), diff(u(x, y, t), t, t))*(diff(u(x, y, t), x, t, t))-(1/8)*(D[10](a))(x, y, t, u(x, y, t), diff(u(x, y, t), x), diff(u(x, y, t), y), diff(u(x, y, t), t), diff(u(x, y, t), x, x), diff(u(x, y, t), y, x), diff(u(x, y, t), x, t), diff(u(x, y, t), y, t), diff(u(x, y, t), t, t))*(diff(u(x, y, t), x, x, t))-(1/8)*(D[11](a))(x, y, t, u(x, y, t), diff(u(x, y, t), x), diff(u(x, y, t), y), diff(u(x, y, t), t), diff(u(x, y, t), x, x), diff(u(x, y, t), y, x), diff(u(x, y, t), x, t), diff(u(x, y, t), y, t), diff(u(x, y, t), t, t))*(diff(u(x, y, t), y, x, t))-(1/8)*(D[9](a))(x, y, t, u(x, y, t), diff(u(x, y, t), x), diff(u(x, y, t), y), diff(u(x, y, t), t), diff(u(x, y, t), x, x), diff(u(x, y, t), y, x), diff(u(x, y, t), x, t), diff(u(x, y, t), y, t), diff(u(x, y, t), t, t))*(diff(u(x, y, t), y, x, x))+(1/8*(-3*(D[8](a))(x, y, t, u(x, y, t), diff(u(x, y, t), x), diff(u(x, y, t), y), diff(u(x, y, t), t), diff(u(x, y, t), x, x), diff(u(x, y, t), y, x), diff(u(x, y, t), x, t), diff(u(x, y, t), y, t), diff(u(x, y, t), t, t))-4))*(diff(u(x, y, t), x, x, x))-(1/8)*(D[1](a))(x, y, t, u(x, y, t), diff(u(x, y, t), x), diff(u(x, y, t), y), diff(u(x, y, t), t), diff(u(x, y, t), x, x), diff(u(x, y, t), y, x), diff(u(x, y, t), x, t), diff(u(x, y, t), y, t), diff(u(x, y, t), t, t))+(1/4)*(D[8](a))(x, y, t, u(x, y, t), diff(u(x, y, t), x), diff(u(x, y, t), y), diff(u(x, y, t), t), diff(u(x, y, t), x, x), diff(u(x, y, t), y, x), diff(u(x, y, t), x, t), diff(u(x, y, t), y, t), diff(u(x, y, t), t, t))*(diff(u(x, y, t), x, x, x));

Now I am trying to get the coefficients of the derivatives of u(x,y,t). So by hand I have done the calculation of taking the coeffient of diff(u(x,y,t),x,x,x) and setting this equal to zero, and then the coefficient of diff(u(x,y,t),x,x,t) and so on. However when I use the coeff function, it will only allow me to compute the coeff of diff(u(x,y,t),x,x,x) and others of third order. However it will not let me use the deriviateves of u of second and first order.

coeff(Lambda,diff(u(x,y,t),x));

this will not work but 

coeff(Lambda,diff(u(x,y,t),x,x,x));

will work.

Any help would be great thanks.

I have a relatively complicated ODE that i am plotting. One of the variables in particular (B[2211], purple line in the graph) should under go an exponential-like decay to zero, but instead flies off into negative territory  (see graph below) despite having a very simple equation:

problem variable rate of change= -problem variable*constant +linear combination of variables that  are always posotive.

My intuition is that this is because i have somehow used the odeplot tool wrong - possibly due to a problem with stepsizes.

Here is a MWE i've made:

aa_problem_MWE.mw

Hi everybody,

Please take the example given in the help pages of DocumentTools[Tabulate] (the one where a cardinal sine is plotted)
Change plot(sin(x)/x) by plot(sin(x),/x, legend=sinc(x))

The legend doesn't appear if the list (named "A" in the help page) is displayed through DocumentTools:-tabulate.

Is it possible to circumvent this problem ?

TIA

Hi all,

I don't know why this file doesn't work anymore! It was ok last week. I even reinstall the Maple on my laptop, but it went wrong again...

Please help me.

Plot_Diff_Temperature.mw

"There were problems during the loading process. Your worksheet may be incomplete."

Pls fix this problem for me. I tried various things. The text in the worksheet is in Danish and contains danish letters (æøå) which may have caused the problem.

Maple Worksheet - Error

Failed to load the worksheet /maplenet/convert/1._Opgaver.mw .
 

Download 1._Opgaver.mw

Download 1._Opgaver.mw

Hi everybody,

I have written a module (let's say MyModule) that  I use as a package in a worksheet (with(MyModule)).

At some point in my worksheet I call the procedure MyProc which is part of MyModule.
I find it not to work as expected. So I modify it within MyModule and generate again the archive which contains this module.

Because my worksheet does a lot of things before the call to MyProc, I would like to test quickly the above modifications.
The idea is to do :
unwith(MyModule):  # packages() no longer exhibits its name
with(MyModule);      # to load the corrected one

Unfortunately, contrary to what happens with a "native" package,  the command unwith(MyModule) is ineffective:

• once done showstat(MyProc) still displays the content of the procedure, and running  the command MyProc(...) proves that it still "exists" in the worksheet
   
• forcing a reload of MyModule ( with(MyModule) ) and acanning again MyProc ( showstat(MyProc) ) reveals the code MyProc had when MyModule has been loaded for the first time.

Is it possible to "free" a user package through the "unwith" command ?

Hope to read you soon, TIA


PS : to be clearer

A worksheet contains  the definition of N procedures, plus the one of MyModule, and ends with the commands to generate an archive file named MyModule.mla.
MyModule is defined that way

MyModule := module()
option package

export Proc1 := eval(:-Proc1),
           ......
           MyProc := eval(:-MyProc),
           ......
           ProcN := eval(:-ProcN):
end module
 

Download aisha.mw

The set and list produced by map (see below) contain duplicates.  How to remove duplicates?
 

Download cp.mw

Hi, I would like to plot multiple curves with arrows pointed at each curve. I don't know how to plot the arrows with values. A similar figure is attached. Thanks for helping . . .

Hi there,

I have a function X that I am trying to plot a phase portrait for against it's derivative dX/dt. I currently have the code:

plot([X,diff(X,t),t=0..10],numpoints=1000) 

which sketches a graph but does not give any arrows to indicate direction.

Could anybody help?

Many thanks

Hi there,

I have a function defined as:

U:=-[0.25*exp(1/2*epsilon*t)*(1/v^2-1+exp(epsilon*t))^(-0.5)]*sin(4*t)

which I am trying to plot on a 2D graph of axes (t,u(t)).

In the specific case I have epsilon=1/10 and v=2

When I try plot(U), maple returns the error message:

Warning, unable to evaluate the function to numeric values in the region; see the plotting command's help page to ensure the calling sequence is correct

Could anybody help me out please?

Many thanks

Hi there,

I have an ode that I want to plot, I am trying to plot 2 different graphs on one graph and have tried using display but cannot seem to add a legend to it. Someone suggested adding a legend to each individual graph before combining them but I cannot find out how to add a legend to a DEplot. My code is as follows:

ode:=diff(u(t),t$2)-0.1*(1-64*u(t)^2)*diff(u(t),t$1)+16*u(t)=0

Q1:=v/4*sin(4*t)+epsilon*(1/8*(v-v^3)*t*sin(4*t)+v^3/128*(cos(4*t)-cos(12*t)))

A:=DEplot(ode,u(t),t=0..10, [[u(0)=0, D(u)(0)=v]], u=-0.5..0.5, linecolor=black, linestyle=dash, title="Numerical Solution"):

B:=plot(Q1, t=0..10, u=-0.5..0.5,color=blue, legend="Regular Perturbation Expansion"):

display([A,B],title="Comparing the regular perturbation expansion to the numerical solution")

Many thanks

Good day everyone,

I'm relatively new to Maple, and I study engineering (not maths), so maybe my problem is related to a bad approach of the equations.

The problem is that I'm asking Maple to do a double integral of a "complex" expression and it only solve the first integral, but not the second.

Here is the code:

https://www.dropbox.com/home/C%C3%81LCULO%20FUERZAS

Thanks.

Dears!

Hope everyone should be fine. I am face to import excel sheet in maple. I saved execl sheet with name "Employees.xlsx" at desktop. When I use the following command
S := Import("Employees.xlsx", 1, "A1:B101");

I got the following error. 

"Error, (in ExcelTools:-Import) Could not open the file"

Please help me to fix this problem. I am waiting positive response. 

Special request to:

@Carl Love
@Preben Alsholm
@acer