Hello everyone,
Gretting from me. I am Md. Abubakar Siddik from Bangladesh.

I have 20 equations  and 20 variables for a system. I want to solve it numerically. 

Any advice ?
system_equation.mw

Thank you in advance for your cooperation. I look forward to hearing from you.

I read a string from file which contains a sequence of Maple commands, all in one string. The commands are separated by ";" in the string. I need to then evaluate all the commands in the string as if I typed them one after the other. 

Here is an example

data:="x:='x';y:='y';sol:=dsolve(diff(y(x),x)=1,y(x));"; #read from database
parse(data);

Warning, extra characters at end of parsed string
x := 'x'
 

I want the result to parse to be as if I typed

x:='x'; 
y:='y'; 
sol:=dsolve(diff(y(x),x)=1,y(x));

I looked at help in parse page, but I do not see what I need to do. It says that 

If the option 'statement' is specified, the string must consist of exactly one Maple statement (which includes expressions). The statement is parsed and evaluated, and the result is returned.
 

But I am not using the statment option. I also tried using this option, no change, same problem.

Is there a way to prase such a string? 

Thanks

  SALUT,

J'ai exécuté la procédure suivante, afin de tracer une courbe (Bézier), mon objectif final est de construire "à l'aide de Maple" une théière (avec des révolutions et des rotations certainement), y at-il des suggestions?

The conditional trigger in the code below does not cause a halt although odeplot shows x dipping to a value below 2.

What is the correct coding of this event to cause a halt when x becomes less than 2?

Does any Maple documentation show examples of working discrete events with conditional triggers?

restart;

DE1 := diff(x(t), t, t) = -x(t)-(diff(x(t), t))+y(t);

DE2 := diff(y(t), t, t) = y(t)-(diff(y(t), t))+x(t);

ICs := x(0) = 2, (D(x))(0) = 1, y(0) = 0, (D(y))(0) = 1;

sol1 := dsolve({DE1, DE2, ICs}, {x(t), y(t)}, numeric, event_initial = true, events = [[[0, x(t) < 2], halt]]);

plots:-odeplot(sol1, [t, x(t)], t = 0 .. 3);
 

In the following case evalhf Int not working. Please help

evalhf.mw

Hi, 

In two lines below Command1 and Command2 have the same value

Command1 := subs([a=1, b=2], a*x+b);
Command2 := eval(a*x+b, [a=1, b=2]);

Are there pros and cons of using one over the other?

Thanks in advance

diff(m(t, x), t)+diff((u(t, x)^2-(diff(u(t, x), x))^2)*m(t, x), x) = 0

How I can change it by using this transform

m(t,x)=u(t,x)-diff(u(t, x), x,x)

to get a new PDE only with u(t,x)

then I need to change u(t,x) by

u(t,x)=u(y)

where y=x−at

How I can do this in Maple?

Hello everyone!

I am struggling to figure out the cause of the problem with Explore command. To put it as simple as possible:

 a := <3, 4, 5>

Explore(a[i], i = 1 .. 3);
Error, (in Explore) bad index into Vector

I am pretty sure that this has to do with an attempt to evaluate A[i] with i not yet defined, but why does Explore behave this way? seq has no such problem:

seq(a[i], i = 1 .. 3);
3, 4, 5

But as soon as I put it into Explore, seq seems to forget all its "special evaluation rules":

Explore(seq(a[i], i = 1 .. 3), b = 1 .. 2);
Error, (in Explore) bad index into Vector

It is probably for the same reason that I can't solve the problem with unevaluation quotes such as: 

Explore('a[i]', i = 1 .. 3);
Error, (in Explore) bad index into Vector
 

What am I doing wrong??

How to find characterstics for the PDE  yzp+2xq=xy  using maple.....plz help me 

I am trying to  solve the system of equations
with(RealDomain);
solve(x^2+y^2+z^2-4*x+6*y-2*z-11 = 0, 2*x+2*y-z = -18], [x, y, z]);

I didn't get the result x = - 4/3, y = -19/3, z = 8/3.

How can I get the solution?

With Mathematica, I tried 
Solve[{x^2 + y^2 + z^2 - 4*x + 6*y - 2*z - 11 == 0, 
  2*x + 2*y - z == -18}, {x, y, z}, Reals]

And got the correct solution.
 

How to plot the solution of pde

pde:=diff(u(x,t),t) =K*diff(u(x,t),x, x); 

I can't step further,  i can't insert boundary value problem, plz help me to solve pde.

Hear u(x,t)->infinity  when t->infinity  and diff(u(x,t),x) =0 when x=0 for all t 

Please ignore my mistake,

If I have a procedure that for example produces a list of times it takes to work out the eigenvectors of a random nxn matrix from n=2..9.

Times:=[seq([n,time(LinearAlgebra[Eigenvectors](RandomMatrix(n)))],n=2..9)]:

If I want to make my data more accurate so that it works out the time it takes to find the eigenvector for each different sized matrix multiple times and then takes an average time (for each n), how would I do that?

Hi I'm trying to make a procedure that will multiply all the diagonal entries of any random matrix together, this is what I have tried so far:

with(LinearAlgebra):
with(ListTools):
Diag := proc(A)
local aux,V,i,n;
V:=[];
n:=RowDimension(A):

for i from 1 to n do 
aux := 1; 
aux := aux*U2(i,i);
end do:

end proc;

but this just produces the last diagoinal entry of the matrix - how do I make the loop multiply the previous number by the next diagonal entry?

another option I've done is to make a list of the diagonal entries, but then I encounter the same problem with multiplication:

Diag:=proc(A)
local n, List;
n:=RowDimension(A);
List:=[seq(A(i,i),i=1..n)]:
end proc:

any help would be greatly appreciated!
 

I recently had a wonderful and valuable opportunity to meet with some primary school students and teachers at Holbaek by Skole in Denmark to discuss the use of technology in the classroom. The Danish education system has long been an advocate of using technology and digital learning solutions to augment learning for its students. One of the technology solutions they are using is Maple, Maplesoft’s comprehensive mathematics software tool designed to meet the unique and complex needs of STEM courses. It is rare to find Maple being used at the primary school level, so it was fascinating to see first-hand how Maple is being incorporated at the school.

In speaking with some of the students, I asked them what their education was like before Maple was incorporated into their course. They told me that before they had access to Maple, the teacher would put an example problem on the whiteboard and they would have to take notes and work through the solution in their notebooks. They definitely prefer the way the course is taught using Maple. They love the fact that they have a tool that let them work through the solution and provide context to the answer, as opposed to just giving them the solution. It forces them to think about how to solve the problem. The students expressed to me that Maple has transformed their learning and they cannot imagine going back to taking lectures using a whiteboard and notebook.

Here, I am speaking with some students about how they have adapted Maple to meet their needs ... and about football. Their team had just won 12-1.

Mathematics courses, and on a broader level, STEM courses, deal with a lot of complex materials and can be incredibly challenging. If we are able to start laying the groundwork for competency and understanding at a younger age, students will be better positioned for not only higher education, but their careers as well. This creates the potential for stronger ideas and greater innovation, which has far-reaching benefits for society as a whole.

Jesper Estrup and Gitte Christiansen, two passionate primary school teachers, were responsible for introducing Maple at Holbaek by Skole. It was a pleasure to meet with them and discuss their vision for improving mathematics education at the school. They wanted to provide their students experience with a technology tool so they would be better equipped to handle learning in the future. With the use of Maple, the students achieved the highest grades in their school system. As a result of this success, Jesper and Gitte decided to develop primary school level content for a learning package to further enhance the way their students learn and understand mathematics, and to benefit other institutions seeking to do the same. Their efforts resulted in the development of Maple-Skole, a new educational tool, based on Maple, that supports mathematics teaching for primary schools in Denmark.

Maplesoft has a long-standing relationship with the Danish education system. Maple is already used in high schools throughout Denmark, supported by the Maple Gym package. This package is an add-on to Maple that contains a number of routines to make working with Maple more convenient within various topics. These routines are made available to students and teachers with a single command that simplifies learning. Maple-Skole is the next step in the country’s vision of utilizing technology tools to enhance learning for its students. And having the opportunity to work with one tool all the way through their schooling will provide even greater benefit to students.

(L-R) Henrik and Carolyn from Maplesoft meeting with Jesper and Gitte from Holbaek by Skole

It helps foster greater knowledge and competency in primary school students by developing a passion for mathematics early on. This is a big step and one that we hope will revolutionize mathematics education in the country. It is exciting to see both the great potential for the Maple-Skole package and the fact that young students are already embracing Maple in such a positive way.

For us at Maplesoft, this exciting new package provides a great opportunity to not only improve upon our relationships with educational institutions in Denmark, but also to be a part of something significant, enhancing the way students learn mathematics. We strongly believe in the benefits of Maple-Skole, which is why it will be offered to schools at no charge until July 2020. I truly believe this new tool has the potential to revolutionize mathematics education at a young age, which will make them better prepared as they move forward in their education.

I need to convert a maple code into a clickable user interface one. How to do it?. Thank you.