Hi,

I'm using Maple on a linux partition and for some time now I can't really use it anymore. For example, when I open a help window, I can't scroll through the content, and scrolling gets stuck if an image needs to be displayed. I think my partition is too full and does not have enough free space left. Doesn't Maple create a temporary file that is too big for the space available?  But I have another partition that is not in the same format as the linux partition but is nevertheless readable and writable. Is it possible, if the problem is a temporary file, that this file is written to this other partition to avoid this storage problem?
Or could it be due to a memory problem (RAM?) that did not occur before?

Say that we have three matrices X, Z, and A of equal size such that Size(X) = Size(Y) = Size(A) = [10 14].

Here, X[i, j] = X[i + 1, j] and Y[i, j] = Y[i, j + 1], i.e. X and Y are the grid in Matlab notation.

i found that countourplot can provide the contour plot for a bivariate function f(x,y). i was wondering whether this can also be done in Maple for matrices. Any help is highly appreciated – thank you,

Fede

Hi,

I want to solve this system of PDEs. Please let me know how I can solve it.

Kindly find both my code written in Maple and the image of the problem.

Best,

PDE.mw

I needed to normalize the eigenvectors of a matrix. (I did not see an option to do this so far in LinearAlgebra). So I figured I just need to map LinearAlgebra:-VectorNorm(x,'Euclidean')  of each vector of the generated eigenvectors matrix,. Where x here means the vector in the matrix. But do not see a way to do it. 

I ended up just using seq, which works fine. But was wondering if there is a way to do it? map function on each column (or each row) and have the result be matrix ofcourse. 

Will show my attempt using map, and then using seq

Sx:=1/sqrt(2)*Matrix([[0,1,0],[1,0,1],[0,1,0]]);
lam,v:=LinearAlgebra:-Eigenvectors(Sx);

Just doing the following does not work ofcourse

map( x->x/LinearAlgebra:-VectorNorm(x,'Euclidean'), v) 

So I used seq

Sx:=1/sqrt(2)*Matrix([[0,1,0],[1,0,1],[0,1,0]]);
lam,v:=LinearAlgebra:-Eigenvectors(Sx);
normalized:=[seq( v(..,i)/LinearAlgebra:-VectorNorm(v(..,i),'Euclidean'),i=1..LinearAlgebra:-RowDimension(v) )];

Will be nice if one can use map or variation of it, which works on either columns or rows at a time.

Maple 2021.2

I am doing some solution for pde :

restart;
with(PDEtools);
with(plots);
alias(u = u(x, y, t), w = w(x, y, t), f = f(w));
pde := diff(u, x, x, x, y) + 3*diff(u, y)*diff(u, x, x) + 3*diff(u, x)*diff(u, x, y) + 2*diff(u, y, t) = 0;
pde2 := subs(u = D(f)(w)*diff(w, x) + u0(x, y, t), pde);

pde3 := expand(pde2);

after this step i want to substitute 
D(f)(w)*D^(3)(f)(w)= (-c/3)*D^(4)(f)(w)

so i apllied command as this :

pde33 := subs({D(f)(w)*(D^(3)(f)(w) = -c/3*(D^(4)(f)(w)}, pde3);

but i not able to replace it !

please help in it ! Thanks!

Hi!

I want to import the data included here to my Maple code:

https://www.gw-openscience.org/GW150914data/P150914/fig2-unfiltered-template-reconstruction-H.txt

There are 3 columns of data: time, NR strain, Reconstructed strain. I am not interested in the middle column; I want to plot the reconstructed strain as a function of time. I could use some help.

Cheers!

Two days ago I have answered a question about using numapprox:-infnorm for functions of several variables. The question is now deleted. Is it possible to find whether it was deleted by the author (even if she/he has used the "best answer" tag)?

Dear all

I compute by hand the bifurcation point of an ode, 
I fouded x=-1/2 a+ 1/2 corresponding to  h= (a+1)^2/4  with 0<a<1 

The same solution is obtained using Maple code. 
I tried to plot the birfurcation diagram to stech with kind of bifrucation ( saddle, Holf . transcritical , periodic, or someting else)
But I get 
Error, (in plots/implicitplot) invalid input: invalid range for first variable

bifurcation_diagram.mw

thank you for any help 

 

PDE:

(a+b)*(u_xx+v_xy)+c*laplacian(u)=0

(a+b)*(v_xy+v_yy)+c*laplacian(v)=0

a,b,c=const.  Initial:u=1/2*sin(2*theta),v=cos(theta)

Text book says: Solve by complex variable method

Dear all

I have a PDEs depend on u1(r,z) 
I would like to decompose u1 as sum of two function c1*r*U(z)+u(r,z) and  , where c1 is constant,  then i would like to substitute u1 in the pde by   c1*r*U(z)+u(r,z) then obtain the corresponding new equation

subs_function.mw

thank you 

Is there a way to make a library file that automatically has the functions/procedures loaded on startup and after it any new or open ".mw" can use functions/procedures from library with no redefinition?

I have a table that includes the numeric and exact solution of a complex PDE.

I want to calculate error between exact and numeric solution. 
Question 1: Which type of error is mostly used for complex solutions? Absolute error or relative error ,ecludian norm error etc.

Question 2: How to calculate absolute error in complex solutions?

 |abs(Exact_Solution)-abs(Numeric_Solution)|

or

|abs(Exact_Solution-Numeric_Solution)|

restart:
interface(rtablesize=19):
Table_1:=Matrix(19,4,{(1, 1) = x, (1, 2) = t, (1, 3) = Exact_Solution, (1, 4) = 
Numeric_Solution, (2, 3) = .58480350959087385609+1.0129093910559867400*I, (2, 4
) = .58480354764257321311+1.0129094569634633407*I, (3, 2) = .2, (3, 3) = .58507\
763625784549559+1.0133841923708911330*I, (3, 4) = .58507767430954485264+1.01338\
42582783677337*I, (4, 2) = .4, (4, 3) = .58590001649935378049+1.014808596732324\
2462*I, (4, 4) = .58590005455105313755+1.0148086626398008469*I, (5, 2) = .6, (5
, 3) = .58727066619506620449+1.0171826316446769860*I, (5, 4) = .587270690527719\
69197+1.0171826737900691093*I, (6, 2) = .8, (6, 3) = .58918956627727806829+1.02\
05062640817160297*I, (6, 4) = .58918959060993155574+1.0205063062271081530*I, (7
, 2) = 1.0, (7, 3) = .59165666981620797589+1.0247794127586756112*I, (7, 4) = .5\
9165677643905044333+1.0247795974348560123*I, (8, 1) = .5, (8, 3) = .59165805893\
555155139+1.0247818187839564608*I, (8, 4) = .59165677643905044333+1.02477959743\
48560123*I, (9, 1) = .5, (9, 2) = .2, (9, 3) = .58919046685310110177+1.02050782\
39247975919*I, (9, 4) = .58918959060993155574+1.0205063062271081530*I, (10, 1)
= .5, (10, 2) = .4, (10, 3) = .58727131671750391922+1.0171837583825905714*I, (
10, 4) = .58727069052771969197+1.0171826737900691093*I, (11, 1) = .5, (11, 2) =
.6, (11, 3) = .58590207620818846348+1.0148121642526747156*I, (11, 4) = .5859000\
5455105313755+1.0148086626398008469*I, (12, 1) = .5, (12, 2) = .8, (12, 3) = .5\
8507958971290229630+1.0133875758542998141*I, (12, 4) = .58507767430954485264+1.\
0133842582783677337*I, (13, 1) = .5, (13, 2) = 1.0, (13, 3) = .5848057178847424\
9287+1.0129132159331652617*I, (13, 4) = .58480354764257321311+1.012909456963463\
3407*I, (14, 1) = 1.0, (14, 3) = .61222010009837745680+1.0603963187852935669*I,
(14, 4) = .61222010009837745677+1.0603963187852935669*I, (15, 1) = 1.0, (15, 2)
= .2, (15, 3) = .60700988526763399480+1.0513719619800970123*I, (15, 4) = .60700\
988526763399480+1.0513719619800970123*I, (16, 1) = 1.0, (16, 2) = .4, (16, 3) =
.60234868471511732616+1.0432985257988700194*I, (16, 4) = .60234868471511732617+
1.0432985257988700194*I, (17, 1) = 1.0, (17, 2) = .6, (17, 3) = .59823621894610\
415849+1.0361755261425513984*I, (17, 4) = .59823621894610415846+1.0361755261425\
513983*I, (18, 1) = 1.0, (18, 2) = .8, (18, 3) = .59467229263079952050+1.030002\
6246900120270*I, (18, 4) = .59467229263079952054+1.0300026246900120270*I, (19,
1) = 1.0, (19, 2) = 1.0, (19, 3) = .59165677643905044330+1.0247795974348560123*
I, (19, 4) = .59165677643905044333+1.0247795974348560123*I},datatype = anything
,storage = rectangular,order = Fortran_order,shape = [])

I want to check whether the solution trial_sol satisfies the following PDE by Maple:

restart:
PDE:=diff(diff(u(x,y,t),x,y)/u(x,y,t),t$2)-diff(diff(u(x,y,t),x,y)/u(x,y,t),x$2)+2*diff((u(x,y,t)^2),x,t);
trial_sol:=(x,y,t)->sqrt(r)*tan((-t*v+x+c*y) *abs(sqrt(r)/(sqrt(2*c-2*c*(v^2)))))/(sqrt(2)*sqrt(v));
pdetest(u(x,y,t)=trial_sol(x,y,t),PDE);

Maple says the trial_sol is not a solution for PDE.

But Mathematica says that it is a solution. What is the problem?

I plotted the following tangent function with Maple and Mathematica for t=4. 

restart:
func:=unapply(-tan((-4*t+x+2*y)/(2*sqrt(15)))/(2*sqrt(2)),x,y,t);
plot3d(func(x,y,4),x=-15..15,y=-15..15);

Maple 3D plot:

Mathematica 3D plot:

I think that Maple shows the asymptotes. Is it possible to close the asymptotes?