I have the following situation:

HB:=Bend(L,a,n);

Bend is a proc, that returns a Record with info based on its parameters. I would like to get access to the name I assign to (i.e. HB) in the proc. Any chance?

Mac Dude

PS: I can of course kludge things by adding an argument to the proc Bend. But I'd like to avoid that.

Hi,

I'm trying to solve the following differential equation numerically with dsolve:

but dsolve gives me this error:

> res := dsolve(DGL, numeric, parameters = [y0, A, B, C, E]);
Error, (in DEtools/convertsys) unable to convert to an explicit first-order system

I think the problem is that I use the wrong solver. Does Maple provide a solver which is capable of solving this kind of equations (nonlinear ODE)?

Thanks in advance!

hello , to solve a differential euqations , maple gave me this error. please help me.

TG.mw

Hello, 

I`m new with the Physics package. I have a Hamiltonian in a lattice written in terms of creation and annihilation operators. The Question is, How can I label a Creation and an Annihiliation operator for each site in the Lattice. WIth this, I can compute mean values and other stuffs associated with the Hamiltonian.

Many thanks in advance

Hi,

  Excuse me, I tried to substract in a series expansion. It works for Taylor-type expansion, but not Laurent-type ones

*********

ffff:=1/(t-3);
ggg:=taylor(ffff,t=infinity,3);
coeff(ggg,t,-1);

ffff:=exp(t);
ggg:=taylor(ffff,t=0,3);
coeff(ggg,t,1);

*********

Maple gives me

Error, unable to compute coeff

1

. My question is, why "coeff" does not work in the first case? how to make it work? Though I can copy the expansion part, assign it to another variable, and "coeff" will work

Excuse me,

  I have the following input

***

fff:=x1^k;
int(fff,x1=0..x2);

***

I would like to obtain

1/(k+1)* (x2^(k+1)), k<>-1

but maple gives me just the same integral. Is there any way to get the expression?

Thank you!

I am trying to make a plot3d on my Surface Pro  3 running Windows8.1.

The plot looks like a ghost.  Pale grey.  It looked nice and colourful when I executed the same command on an older computer a few hours ago.  (I know it was exactly the same command because I saved the file on my old computer and then opened in on the Surface Pro 3)

Is there a way to fix this?

plot3d(-x^2+y^2-3*x+2*y+100, x = -5 .. 8, y = -5 .. 5, transparency = 0, lightmodel = light1, glossiness = 1, filled = true, style = wireframeopaque, shading = zhue, view = [-5 .. 10, -5 .. 8, 0 .. 150]);

 OOPS!  Now the problem has corrected itself.  

I'm getting worried about all the weird things Maple is doing on this Surface Pro 3.  I'm trying to make up a final exam tonight (the exam is tomorrow).

I have downloaded MaplePlayer on my iPad.   I see that it comes with a number of "pre-recorded" programs that it can run.  Is there a way to have it run a Maple worksheet that I have written?   If so, how do I use this app to open an existing worksheet? 

Also, are there any plans for this app on the Android platform any time soon?

I have written a program and I would like to embed a check near the beginning to see if input data was entered correctly.  I have written an "if statement" to check on this and I would like the program to stop execution at this point if the "if statement" criteria are met.   I get an error saying that this command is disabled.   I have tried "stop", "end" and "quit," as I understand that they are all the same.

TwoEquations.mw

Download TwoEquations.mw

Hi all,

I have a simple transfer function like

I want to calculate the amplitude ratio and the phase shift.

Without maple I would set s=I*omega and solve for real and imaginary part to obtain the phase shift and amplitude ratio.

Is there any possibility to do that in Maple more easily?

Hi,

When I run a maple program which take a long time (in command line), I have this kind of message every second:

"memory used=43867.3MB, alloc=147.3MB, time=856.28"

Does there exist any way to avoid this display ?

Thanks in advance.

How would one in Maple solve this, which is an inequality equation in some variables, which can be nonlinear, with constraints on range of each variable. I.e. I want to find conditions on the variables to make the inequality satisfied.

In Mathematica, I use the Reduce command

Clear[x, y];
eq = 1/2 - x + x^2 - y + y^2;
Reduce[{eq > 0, 0 < x < 1 && 0 < y < 1}, {x, y}, Reals]

How would one do the same in Maple? I tried solve, but can't give constraints.

restart;
eq:=1/2 -x+x^2-y+y^2:
solve(eq>0 , {x1, x2});

So I need to do the same as in the Mathematica command, but in Maple. I do not want numerical solution, but algebraic as shown above.

Using Maple 18.2 on windows.

Hello people in mapleprimes,

I want to ask a question about modification of expression.

Basically, what I want to do is to change the expression of sqrt((-a)^2) to sqrt(a^2).

The expression I want to modify is this:

aa:=phi[n, j] = a[j, D]-a-sqrt((-a[j, D]+a+tau[n, j])^2+4*gamma*f[c, n, j]/L[j])

I want to change this to 

phi[n, j] = a[j, D]-a-sqrt((a[j, D]-a-tau[n, j])^2+4*gamma*f[c, n, j]/L[j])

To do this, I wrote as 

subs(sqrt((-a[j, D]+a+tau[n, j])^2+4*gamma*f[c, n, j]/L[j]) = sqrt((a[j, D]-a-tau[n, j])^2+4*gamma*f[c, n, j]/L[j]), phi[n, j] = a[j, D]-a-((-a[j, D]+a+tau[n, j])^2+4*gamma*f[c, n, j]/L[j])^(1/2))

Or, I wrote as 

subs(op([2,3,2,1,1],aa)=(a[j, D]-a-tau[n, j])^2,aa)

If there is better ways, please tell me them.

Best wishes.

taro

I would be grateful if anyone would comment on the compatibility of Maple 18 and MacOS 10.10 (Yosemite).