Hello everyone,

I want to know, how we can plot residual errors of the numerical scheme offered with dsolve command? This plot should show that the errors are in admissible range which indicates that the numerical scheme offers high accuracy.

For example, we have a bvp

dsolve({diff(y(x),x$2)-2*y(x)=0,y(0)=1.2,y(1)=0.9}, numeric,method=bvp[midrich]);

How to plot "Residual Error vs x" in this specific case?

 Thanks

Dear Maple users

I am trying to simulate the distribution of Q-values (Karl Peason) in a Contingency table. In that regard I need to use a two dimensional iteration. It require quite a lot of time to perform the computations. Using the values below, it required 1.3 mio iterations and took about 5 minuttes on my computer. My question is if there are ways I can speed it up? It might be using different commands, which are executed faster, performing computations in the...

i have a list of numeric values like this:

r:=[a,b,c,....]

now i want to calculate the quantity

s:=lambda-r^2

which in turn should give me a list again whose entries are:

[lambda-a^2,lambda-b^2,...]

but just doing

s:=lambda-r^2 doesnt work.

lambda is an arbitrary number

 

a,b ; a^2, b^2, a*b = b*a

is a presentation

a and b are permutation group

a*b = b*a is relation

i am not sure a^2 or b^2 are generator, i guess they are

so how to find a and b which are permutation group?

 

is it a,b ; a^2, b^2, a*b = b*a     or      a,b ; a^2=1, b^2=1, a*b = b*a  ?

 

if a^2, b^2, a*b = b*a , i do not know what is a^2 if a^2 = 1

multiplication = composition = permmul

it is like matrix multiplication that has right or left multiplication

when deal with words

a1*a2*a1^(-1)

it will become a2, how to maintain a1*a2*a1^(-1)

because i expect to do some transformation

permutation matrix
1 1

0 1
become group of permutation

1 1 2

1 2 2

fgen:= convert([1,2,2], disjcyc);

however, first row is not 1,2,3

how to do?

Dear Maple users

In a short Maple program I am dealing with a collection of random samples from a uniform distribution. My problem is that every time I call a procedure creating a sample, I get the exact same one! Every run needs a different seed. How do I get a new 'random' sample? I could probably let Maple create all from scratch calling the Sample command with a two-dimensional range, but this will requre a big memory ...

 

Here is part of my code:

f

1 2 3 4

3 2 4 1

g

1 2 3 4

2 4 3 1
f := permgroup(4, {[[1, 3, 4]], [[2]]});

g := permgroup(4, {[[1, 2, 4]], [[3]]});

mulperms(f,g);
Error, (in permgroup) generators must represent products of disjoint cycles, but [2] does notError, (in permgroup) generators must represent products of disjoint cycles, but [3] does notError, (in convert/plist) bad index into Array

Hello. I am interested in displaying the content of data structures, which has me using the command interface, to instruct for a wider visibility of these.

However, when I typer and execute the command, it simply does not take effect at the first execution, but it requires for me to re-execute it, in order for it to actually display the proper result.

Any explanation for this? To be more specific, this is what I want to instruct:

Hi, 

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Dear all

i am writing some differential equations with Maple. I'd like now to generate the Matlab code and let them run. Unfortunately I need the closed form but Maple does not distinguish (at first sight, of course) between time functions and parameters. But what in Maple is a time function, will be an array in Matlab. Unfortunately in Matlab environment the array product is carried out by the meaning of the element-by-element command: ".* " .

Using CodeGeneration[Matlab...

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@acer My question is about highly oscillatory integral.I wanna integrate 
int(int(f(x,y)*exp(i*w*g(x,y),y=0..1),x=0..1)) which is higly oscillatory integral in a triangle with vertices  (0,0),(1,0),(1,1) and with g(x,y)=x^2+y^2. Since g(x,y) has stationary  point at (0,0), I have to interpolate f(x,y) except (0,0) but also quite close to (0,0). The problem is that since...

Good day, Is it possible to plot multiple (more than two) functions with 'dualaxisplot'?I've found some information about it on the Internet, which helped me out a lot, but I still don't know how to put in multiple functions in one dualaxisplot.For example I would like to plot a figure which consists of four functions, all of them having their own domain(!).Three of them are related to the 'left' y-axis, and the fourth function is related to the 'right' y-axis.Comment: I wanted to insert the formula over here, which I use to plot the dualaxisplot, but the 'dualaxisplot-command' isn't working ("You have entered an invalid Maple plot command").So for example, I do know how it works with two formulas, like:dualaxisplot(plot(2x,view=[0..10,0..20],labels=[x,left=2x],legend=2x),plot(x^2,view=[0..10,0..100],labels=[x,right=x^2],legend=x^2,color=blue)); Now I can independently change the left and right y-axis like I want to. Now I would like to have the shape of the next graph:The trhee formulas which belong together, and that I want to relate to the left axis (making one line), consist of: horziontal line, linear line, horizontal lineThe other line I want to relate to the right y-axis, which is a linear line. So I can write the four functions for example like:restart;with(plots):eq1:=50,x=0..3:eq2:=(50/(5-3))*(5-x),x=3..5:eq3:=0,x=5..10:eq4:=10x,x=0..10: I thought I could 'join' the (first) three functions by using the '{' and '}' symbols, but that isn't working either. Somebody has a suggestion?Or that it just isn't possible at all.... Thanks anyway for thinking along. Greetings, Frank