I am trying to solve the folowing ODE with initial conditions t0=0,v0=0 and tf =80 with step 0.01 but the matrix that appears is not having the values!please help

Download runge_kutta4.mw

What's the best way to get the eigenvector associated with a certain eigenvalue?

Specifically, given the nature of my matrix A, I know that there ALWAYS exists an eigenvector with eigenvalue 1.  Is there a quick way to extract this without looping through the output of Eigenvectors() and checking each one?

Hello,

I'm modeling the simple DC motor system in Maple.
The equations describing the system;

eq1:=J*diff(theta(t),t,t)+b*diff(theta(t),t)=K*i(t):
eq2:=L*diff(i(t),t)+R*i(t)=V(t)-K*diff(theta(t),t):
DCMotor:=[eq1,eq2];

First, I create the system using DiffEquation:

Sys:=DiffEquation(DCMotor,[V(t)],[theta(t)]);

And now I have problem. The input var is V(t) (input voltage) and the output var is theta(t) (position of the rotor).

But I wont to have in output var not position of the rotor but speed of the fotor - diff(theta(t),t)

How to set output var for diff(theta(t),t) (the speed of the motor)?

Best

Rariusz

Hi,

I'd like to create a graded drag and drop exercise so that my students can click on an item and place it into various places (one of which is the correct place). I don't think any of the Question types support this though .. is there a way to build such a quesiton in Maple TA ?

Thank you for your help!

Elisabeth

Dear All

I want to use subs command to replace products in expression with entries from matrix. When I use "subs" command it returns same result as original without any substitution. But when I use "algsubs", it works fine, but is complicated to apply if there are large number of substitutions.

Please see followings:

Download Subs_not_giving_result.mwSubs_not_giving_result.mw

Regards

plot3d(x^2+y^2, x = -1 .. 1, y = -1 .. 1);

i searched this 

http://www.maplesoft.com/support/helpJP/Maple/view.aspx?path=NAG/d06abc

and

DelaunayTriangulation(points) in help file

is there any example to show how to use these?

Hi all.

1. When plotting the function y=(x-1)/(x-2) on Maple 2016, the asymptote along with the actual curve is drawn as "solid lines/curves".  The asymptote should have been drawn as a dotted line to indicate that x=2 is an asymptote so as to distinguish itself from the actual curve.   This confuses my students.

2. The other question is if I modify the equation to y=1+ (x-1)/(x-2), the plot only shows the asymptote at x=2 (again, a solid line).  There should be another asymptote at y=1, which is not shown.

Can someone please advise if Maple would fix this in the next update?    If not, how should one "fix" this when graphing such functions?

Many thanks.

Hello, I have the system of equations in many vars as below, I want to make an implicit plot in Maple with the projection on 3 vars, for example, in this case (x,y,t1). The range is x[-10,10], y[-10,10], t1[-Pi,Pi] and the rest of the vars are [-Pi,Pi]. Does anyone know how to do it? We have also the inequalities in the system.

f1:= cos(t1)+1.35*cos(p1)-x;

f2:= sin(t1)+1.35*sin(p1)-y;

f3:= cos(t2)+1.35*cos(p2)-x +1.15;

f4:= sin(t2)+1.35*sin(p2)-y;

f5:= cos(t3)+1.35*cos(p3)-x+0.575;

f6:= sin(t3)+1.35*sin(p3)-y +0.995;

f7:= cos(t1)*cos(t2)*cos(t3)*sin(p1)*sin(p2)*sin(p3)-cos(t1)*cos(t2)*sin(t3)*sin(p1)*sin(p2)*cos(p3)-cos(t1)*sin(t2)*cos(t3)*sin(p1)*cos(p2)*sin(p3)+cos(t1)*sin(t2)*sin(t3)*sin(p1)*cos(p2)*cos(p3)-sin(t1)*cos(t2)*cos(t3)*cos(p1)*sin(p2)*sin(p3)+sin(t1)*cos(t2)*sin(t3)*cos(p1)*sin(p2)*cos(p3)+sin(t1)*sin(t2)*cos(t3)*cos(p1)*cos(p2)*sin(p3)-sin(t1)*sin(t2)*sin(t3)*cos(p1)*cos(p2)*cos(p3);

f8:= cos(t1)*sin(p1)-sin(t1)*cos(p1) >= 0;

f9:= cos(t2)*sin(p2)-sin(t2)*cos(p2) >= 0;

f10:= cos(t3)*sin(p3)-sin(t3)*cos(p3) >= 0;

Consider you have an expression like:

f := (125*x^3+525*x^2*y+735*x*y^2+343*y^3-36*z^2)/(-216*z^3+25*x^2+70*x*y+49*y^2)

By hand and spending much time maybe we can find out so far that:

f := ((5*x+7*y)^3-(6*z)^2)/((5*x+7*y)^2-(6*z)^3)

I thought that the code `combine(f)` would give us the second one, but it didn’t. Is there anything obvious I cannot see?

Thanks for the time.

I am fairly new to Maple and cannot figure this out.

I'm having some trouble in computing formally the derivatives of
some composite functions

h:= x -> f(g(x)),

imposing conditions on the unknown functions f and g.

For example, I cannot find a way to impose g'(0)=0,
such that the computation of

h'(0)

simply gives 0.

Thank you in advance!

Download Test_pile.mw

Good Evening Maple Community,

Can anybody please help in the attached file. Highlighted in yellow are the three equations I'm trying to program in Maple procedure, but could not get any output due to an error message. Please Help.

Boyer 

Is this what is supposed to happen when linking Maple to Matlab?  I was hoping it would open the actual Matlab program and write variables to the current worksheet.  I'm I missing something?

Nothing even pops up on the Matlab Command window. What good is this?

I want to define a proc in Maple which gets an integer n and gives a set of arrays like {1,2,3}^n, meaning {[a[1],...,a[n]]|for all 1<=i<=n a[i] in {1,2,3}}. For a fix n, obviously one can use n-for, for example when n is 2

A:=Array(1..3,1..3):
for a[1] from 1 by 1 to 3 do
 for a[2] from 1 by 1 to 3 do
  A(a[1],a[2]):=[a[1],a[2]];
 end for:
end for:

But when n is not fixed, how can I tell Maple to consider n for?! Also how can ask him to make a n-dimensional array?

Hi 

I have 3 equations

eq1 := vs = (Rs+Z)*i1+Z*i3

eq2 := A*vi = Z*i1+(Z+Rf+ro)*i3

eq3:= vo = (Rf+Z)*i3+Z*i1

and I want to solve for vo/vs . How to do that ?

the expected solution is 

Hi;

Could anyone help me to compute the lie derivative of the function h:R^3-->R with respect to the vector-valued function f:R^5-->R^3 below?

f(x,y,L,u,v) = [x + u;
               y + v;
               L]

and 

h(x,y,L) = sqrt((y-x)^2 + (L)^2)

Thank you in advance.