i have a non linear equation that depends on three variables e, theta and z.

i have done calculations to calculate e while varying theta and z. theta varied among the vector [0, Pi/4, Pi/3, Pi/2] and z was varying between 1 and 20

when plotting my data it gives the following plot where z is represented on the x-axis and each curve correspond to one theta

i am currently able of fitting one plot to one equation i would like to fit the data points using the nonlinearfit function and to only get one equation for all the plots. is that possible in maple or not

I am having an issue with Physics[Vectors] in Maple 17, specifically an interference with PDEtools:-dchange. My apologies, this post is lengthy & a bit messy. I did upload a worksheet with the code; link at the end. The upload exhibits the UNWANTED behaviour in Maple 17.

Here are a few lines of code that exhibit the WANTED behaviour (change of variable and solving a de). it is run in Maple17 with Physics loaded but NOT Physics[Vectors]. The paste into Mapleprimes looks too messy to be useful so I am just showing the relevant lines; the file has everything:

-(diff(E1_(x, y, z, t), x, x))-(diff(E1_(x, y, z, t), y, y))-(diff(E1_(x, y, z, t), z, z)) = -mu*epsilon*(diff(E1_(x, y, z, t), t, t));

PDEtools:-dchange({x = r*cos(theta), z = r*sin(theta)}, -(diff(diff(E1_(x, y, z, t), x), x))-(diff(diff(E1_(x, y, z, t), y), y))-(diff(diff(E1_(x, y, z, t), z), z)) = -mu*epsilon*(diff(diff(E1_(x, y, z, t), t), t)), simplify);

subs(E1_(r, theta, y, t) = R(r)*exp(I*(-k*y+omega*t)), -((diff(diff(E1_(r, theta, y, t), y), y))*r^2+(diff(diff(E1_(r, theta, y, t), r), r))*r^2+(diff(E1_(r, theta, y, t), r))*r+diff(diff(E1_(r, theta, y, t), theta), theta))/r^2 = -mu*epsilon*(diff(diff(E1_(r, theta, y, t), t), t)));

dsolve((5));

So far this is all as expected.

Now I rerun this thing with Physics[Vectors] loaded rather than just Physics. Everything looks the same until I get to the line starting with subs(E1_ :

subs(E1_(r, theta, y, t) = R(r)*exp(I*(-k*y+omega*t)), -((diff(diff(E1_(r, theta, y, t), y), y))*r^2+(diff(diff(E1_(r, theta, y, t), r), r))*r^2+(diff(E1_(r, theta, y, t), r))*r+diff(diff(E1_(r, theta, y, t), theta), theta))/r^2 = -mu*epsilon*(diff(diff(E1_(r, theta, y, t), t), t)));

plus many more lines of expressions. I am not sure what is going wrong; but after the dchange the code behaves funky: I have had simplify producing similarly weird expressions etc.

Note that on Maple 15 this all works as expected and no issues show up for me. If the version of Physics I have on Maple 17.02 is bad; how do I change that? (I have not tried to update Physics separately, and it isn't obvious to me where to find it for Maple 17). It is sort-of an issue as I want to use this as a demo for students, who in fact will be running Maple 18... but I am stuck at 17 (and often using 15 at home) so I need this to work there (17), too.

TIA,

Mac Dude

dchangeTest.mw

AOA... Dears! When i solve the following differential equations

-(diff(lambda(s), s))-2*(diff(lambda(s), s, s))-(diff(lambda(s), s, s, s)) = 0

i got

lambda(s) = _C1+_C2*exp(-s)+_C3*exp(-s)*s

 here _C1,_C2 and _C3 are constant of intergration but i want the constant of integration of the following type

C[1],C[2] and C[3]

due to some reson pl help

Hi,

I have written a for-end loop and put all the outcomes of the loop in a matrix and now I want to plot these results but for some reason maple won't plot the matrix in a correct way. If I copy-paste the matrix into an new file maple plots it correct. What is the reason that maple won't plot it in my original file?

Here is my file. 

restart;
Parameters
L := 20; Q := 20; n := 8; h := 3; EAv := 1;
Mat := Matrix(10, 2, storage = sparse);
a := 1;
loop L1
for L1 from .6 by .1 to 1.5 do
L1 := L1;
L2 := 2*L1;
L3 := 1.6*L2;
L4 := (1/2)*L-L1-L2-L3;
alfa1 := evalf(arctan(h/L1));
alfa2 := evalf(arctan(h/L2));
alfa3 := evalf(arctan(h/L3));
alfa4 := evalf(arctan(h/L4));
F4 := (1/2)*Q*L4;
F3 := (1/2)*Q*L3+(1/2)*Q*L4+F4;
F2 := (1/2)*Q*L2+(1/2)*Q*L3+F3;
F1 := (1/2)*Q*L1+(1/2)*Q*L2+F2;
w1 := evalf((1+sin(alfa1)^3)*F1*L1/(EAv*sin(alfa1)^2*cos(alfa1)));
w2 := evalf((1+sin(alfa2)^3)*F2*L2/(EAv*sin(alfa2)^2*cos(alfa2)));
w3 := evalf((1+sin(alfa3)^3)*F3*L3/(EAv*sin(alfa3)^2*cos(alfa3)));
w4 := evalf((1+sin(alfa4)^3)*F4*L4/(EAv*sin(alfa4)^2*cos(alfa4)));
kkm := (w1-w2)^2+(w2-w3)^2+(w3-w4)^2; Mat(a, 1) := L1;
Mat(a, 2) := kkm;
a := a+1
end do;

with(plots);
pointplot(Mat);

Hi,

I have this set of equations but maple won't solve the three variables and it gives an 

Error, (in solve) cannot solve for an unknown function with other operations in its arguments. This are the equations with unknowns, alfa1, alfa2, and alfa3.

eq1 := 3*(1+sin(alfa1)^3)(30/tan(alfa1)+60/tan(alfa2)+60/tan(alfa3))/(sin(alfa1)^2*cos(alfa1)*tan(alfa1)) = 3*(1+sin(alfa2)^3)(30/tan(alfa2)+60/tan(alfa3))/(sin(alfa2)^2*cos(alfa2)*tan(alfa2));

eq2 := 3*(1+sin(alfa1)^3)(30/tan(alfa1)+60/tan(alfa2)+60/tan(alfa3))/(sin(alfa1)^2*cos(alfa1)*tan(alfa1)) = (90*(1+sin(alfa3)^3))/(sin(alfa3)^2*cos(alfa3)*tan(alfa3));

eq3 := 3/tan(alfa1)+3/tan(alfa2)+3/tan(alfa3) = 25/2;

solutions := [solve({eq1, eq2, eq3, alfa1 > 0, alfa2 > 0, alfa3 > 0}, {alfa1, alfa2, alfa3})];

Can anyone help?

How can I solve a differential equation set of the type,

dy(x)/dx +y^2 =P(x); dP(x)/dx = R(P) numerically

Hi all,

As we know that the indefinite integral in Maple is defined up to a piecewise constant.

For example,

Due to the indeterminate range of variable n, int returns the piecewise function.

But in the other similar case, we get a generic solution rather than a piecewise function,

Why not to returns the result like this,

Thanks for any help.

How do I plot the graph of 3 functions into one page (that is, as a series). Thank you.

Please this is urgent! I can't seem to be able to upload my job on here.

Thanks.

Hi Everyone, i have question about Piechart.. http://www.mmsonline.com/cdn/cms/Sandvik-pie-chart.jpg

is something like this possible in Maple?

Thank you

Hello guys,

I'm starting to learn MAPLE this week, so first of all I'm sorry for my lack of knowledge about the software. 

I got a worksheet with a ready code, and i'm trying to run it, but I'm receiving an error message that I don't know how to solve, by the fact that I don't know very well yet. But I need to run this URGENTLY, so my hope is that you guys could help me.

The line of code is the following: 

S1:-Results(solutionpoint);for cont2 from 1 to 2 do VNUM[jj,cont2]:=(rhs(S1:-Results(solutionpoint)[de+s+m+cont2]))end do;seq(-add(v[k]*x[jj,k],k=1..de)+add(u[r]*y[jj,r],r=1..s)<=0,j=1..n);seq(add(u[r]*y[jj,r],r=1..s)-add(v[k]*x[jj,k],k=1..de)<=0,j=1..n),

And the error message is the following: "Error, invalid sequence". I think that maybe is something really simple like a comma or something like that. Can you please help me? Thank you very much

Hi,

I would like to compute the elements of the permutation group, let us say S10 or S20.

Is there any method to compute all the elements.

And can we make a list of the tranposition and cycles.

Many thinks.

Dear Colleagues,

1) is there any way to plot the difference of two ode solutions? Smth like display(p1-p2)?
2) is there a way to add a regular plot, i.e. explicit function to the set of plots? I need to have regular plotsand ode plots all together. 

So if you are given a 3x3 matrix i was just wondering how to use plot3d and plot the 3 column vectors given by it?  Thanks.

Hello,

I have a quite long document (around 200 equations + comments).

I need to share my document with collegues.

However, they don't have maple et moreover i would like only to give them my work in a paper format and in a synthetic way. Indeed, they only need to see the main steps of my calculation.

Consequently, i need to make a synthetic presentation of the work i have done on a classic maple worksheet.

For that purpose, i believe that i have 2 ways to do.

1) Create a slideshow. However, i find the mode not very complete in Maple ? Indeed, for the moment, when i have a big section, i didn't manage to scroll on it so as to read the whole section.

2) create a document mode and emphasize only the main equations. 

Questions:

1) What is the best solution for you so as to make a presentation of a work made with classic worksheet?

2) Is it possible to transform a worksheet in a document mode? and if yes, how?

3) Have you some ideas to compact the calculation (or emphasize only the main steps) ?

Thank you for your help

im solving 6 ODE which is the equations are unsteady with boundary conditions.. the program can be run when A=0 but when A=0.2 or others value .. its cannot be run... A means for unsteadiness... before this i solve for steady equations.. this is first time i solve for unsteady using maple.. anyone know where i am wrong??? thanks for helping :)

Download unsteadyManjunatha.mw