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Hi, Question 1: Is it possible to have names using subscripts? I've tried a few names with subscripts. Sometimes it works, sometimes it doesn't. Question2: There must be a faster way to write greek letters using the keyboard instead of going to the greek palette and clicking the greek letter you want. I wasn't able to find how to do that yet.

I want to implement from the following,

> A := `<|>`(`<,>`(6, 2, 1, 6, 8, 3), `<,>`(4, 3, 7, 1, 7, 2), `<,>`(3, 7, 2, 4, 3, 9));

> b := `<,>`(55, 37, 40, 33, 60, 75);

the procedure:

A x X = B
X = A x BA = U x S x V (Singular value decomposition of A)
A = V x S x U(Generalized inverse or pseudoinverse of A)
X = V x Sx Ux B

Least square fit solution
x = 2.63293929474354
y = 3.66652382290048

I'm just learning ODEs and have a textbook problem I'm trying to plot in Maple 13. For the ODEs, In the first year I have a certain behaviour (contaminated water flows into a pool) and in subsequent years fresh water enters the pool. I'd like to show both behaviours on the same plot. How would you do this? Here is what I did to make two separate plots: In the first year - I have contaminatation of a pool: ode1 := diff(q(t), t) = 3-3*q(t)/10^4 DEplot(ode1, q(t), t = 0 .. 8760, [q(0) = 0], title = "contaminant accumulation in the first year")

I want to show which parts of a sequence of plots were obtained later.

The program, written with a huge help from Mapleprimes forums (thanks!) draws some (for example, 200 but it varies) small plots and then paints all of them on one picture. It would be more clear if one could see what happened first. I am thinking of different colours for consequtive plots but not sure that know how to use them well.

If it may be important, the program is below. I would appreciate any help.

 

printlevel := 4;

iter := 200;

"User-selection of 

Hi all in my (very long) code I deal with many dozens of procedures that use a lot of global variables. I declare all of them in the classic way: a:=proc(b, ..., c) local ... global g1, g2, ..., gn; body end proc; I was wondering if there is a way to create a global variable containing the names (not the values) of the global variables g1...gn, so that I can use this variable to pass all the global to the procedures, instead of having to write all of them every time... Thanks S.

Is Maple able to recognize Excel sheets, or maybe other data structures to which I can export Excel tables and have them represented as Arrays or tables or anything else in Maple?

E.g. I have the following Array:

A:=Array(1..3,1..5,[[11,12,13,14,15],[21,22,23,24,25],[31,32,33,34,35]]);

Now I´d like to shuffle the rows of that Array randomly.

How may I do that most efficiently?
 

I think I know why they are the same but they shouldn't be. 

If I pointplot3d with symbol=sphere I get what I expect.  When I use symbol=circle I would expect a flat circle to be drawn.  Is this an option that was missed?  or is it that Maple just didn't carry the command over to 3d land?

 

Dear all

I have a problem with a non linar equation systems. Basically it takes long time  to show me the results

The systems is the following,

R1 := -(1-y)*sqrt(1-x^2)-x*sqrt(1-y^2)+(1/4)*y*(x*sqrt(1-z^2)-z*sqrt(1-x^2))*J = 0;
R2 := -y*(sqrt(1-z^2)+sqrt(1-x^2))+(z+x)*sqrt(1-y^2)-(1/4)*sqrt(1-y^2)*(x*z+sqrt((1-x^2)*(1-z^2)))*J = 0;
R3 := -(1-y)*sqrt(1-z^2)-z*sqrt(1-y^2)-(1/4)*y*(x*sqrt(1-y^2)-y*sqrt(1-x^2))*J = 0;

solve({R1,R2,R3}, {x,y,z}) assuming J>0

Could one help me?

Thanks in advance

Daniel

Hi all I'd like to have a for that runs for the pilot index inside a list of names, and that saves, for each value of the index a variable in an outer file. My problem is that I want the both the variable's name and the file's name to contain the name of the index, and I cannot obtain this behavior, as save asks for a name, not a command. My code would be something like A:=[a,b,c]; for i in A do cat(Mickey_,i):= something; #### that will correctly create Michey_a, Michey_b and Michey_c

Am I missing some justification for this last one?

> zip(`/`,Array([3]),Array([9]));
                                     [1/3]
 
> zip(`/`,Array([3],datatype=integer[4]),Array([9]));
                                     [1/3]
 
> zip(`/`,Array([3]),Array([9],datatype=integer[4]));
                                     [1/3]
 
> zip(`/`,Array([3],datatype=integer[4]),Array([9],datatype=integer[4]));
                            [0.333333333333333315]

Please help me Prims Code. Where am I wrong? Thanks. with(GraphTheory): G := Graph( { [{1, 2}, 3], [{1, 3}, 24], [{1, 4}, 35], [{1, 5}, 16], [{2, 3}, 5], [{2, 4}, 6], [{2, 5}, 17], [{3, 4}, 7], [{3, 5}, 38], [{4, 5}, 19] } ); DrawGraph(G); Prims := proc(G::Graph) local n, A, visited, i, j, k, min, a, b, T; k := 1; min := 999; T := Graph(0); A := WeightMatrix(G); n := NumberOfVertices(G); visited := { op( seq( 0, i = 1..n) ) }; visited[1] := 1; while k <>

Please help me DFS Code. Where am I wrong? Thank you.