Hi

 I have a problem why the result does not appear..my code are:

> P := array([[8, 4], [8, 3], [8, 2], [7, 1], [6, 0], [5, 0], [4, 0], [2, 1], [1, 1], [1, 4]]);

> for j from 2 to 5 do k[j] := j+1;

x[j] := add(P[j, 1], j = j-1 .. j+2);

X[j] := add(P[j, 1]^2, j = j-1 .. j+2);

y[j] := add(P[j, 2], j = j-1 .. j+2);

Y[j] := add(P[j, 2]^2, j = j-1 .. j+2);

xy[j] := add(P[j, 1]*P[j, 2], j = j-1 .. j+2);

cx[j] := evalf(x[j]/k[j]);

cy[j] := evalf(y[j]/k[j]);

c11[j] := evalf(X[j]/k[j]-cx[j]^2);

c22[j] := evalf(Y[j]/k[j]-cy[j]^2);

c12[j] := evalf(xy[j]/k[j]-cx[j]*cy[j]);

C[j] := evalf(Matrix(2, 2, [[c11[j], c12[j]], [c12[j], c22[j]]]));

E[j] := Eigenvalues(C[j]);

if E[j][1] > E[j][2] then lambda[j] := E[j][2]/(E[j][1]+E[j][2]) else lambda[j] := E[j][1]/(E[j][1]+E[j][2])

end if;

end do;

the If function does not work and the result does not appear. Is there any problem in my code.

 Thanks

I was asked to transform (x+y)^2+(1)/x+y into ((x+y)^3+1)/x+y, I have tried nomer/denom, but i don't how to factorise the nomer bit into (x+y)^3+1 because maple factorise it differently by default. therefore, it would be grateful if anyone can help me with this...please?

I am trying to run the application "The Cosmic Travel Planner" by Christian Bar (CBaer), uploaded on August 21, 2013 on Maple cloud (Mobius@admin). I use the left panel of GUI where "MapleCloud" is opened. While opening the application GUI asks my permission for running some code automatically. After my 'YES' Maple gives me an error:

Startup Code Error
0, "permission denied: no read access (%1)", "C:\Users\Andriy\MapleLib"

I tried to give the permission to folder "C:\Users\Andriy\MapleLib" however unsuccessfuly.

OS: Win 8

Could you help me with this Error? Thank you.

I have an equation x²y-3y³x=0. I want to find the slope of the graph at the point (3,1) , that is the derivative at that point. I was told it was possible to do this in one line of command, so I was just wondering if anyone knoew how to do this. Any ideas would be helpful. Thanks in advance.

Hi

I have entered two functions and got a solotion for them:

Now i want to know if there is someway Maple can do this automaticly:

So that i not have to do like i did here, manuel copy-paste the values into the function, or re-enter them.

Using Maple 17.02 on Windows 64-bit, but i guess that makes no differance, since it's java :) 

Try makeing it simple, i'm new with Maple.

Thanks in advance!

Emil Kristensen

PDE.mw

Hi i attach the file that i have problem with.I guess it is not the first problem with datatype=float[8], but i will appreciate if someone could help me with it.

After calling pdsolve i get the answer in the module "structure", i try to plot it and i get :

Error, (in pdsolve/numeric/plot) unable to compute solution for t<HFloat(0.0):
unable to store [.02091392039809]-5.00000000000000 when datatype=float[8]

I am not sure how to interpret it and what should i change to make it work.

My PDE is a Bellman equation and my problem is that i actually know only one boundary condition "icond", is there a way to solve it without other conditions?

Thank you

I gave this function:

g := -2-k[1](lambda*alpha[2]*k[2]+alpha[1](-2-2*k[2]+k[2]*lambda^2))+k[1](lambda*alpha[2]*k[2]+alpha[1](-2-2*k[2]+k[2]*lambda^2))*lambda(lambda*alpha[2]*k[2]+alpha[1](-2-2*k[2]+k[2]*lambda^2))^2

I would like to factor out or to collect:   (lambda*alpha[2]*k[2]+alpha[1](-2-2*k[2]+k[2]*lambda^2))

I use following command: collect(g, lambda*alpha[2]*k[2]+alpha[1](-2-2*k[2]+k[2]*lambda^2))

Nevertheless, I receive an error ...

Error, (in collect) cannot collect lambda*alpha[2]*k[2]+alpha[1](-2-2*k[2]+k[2]*lambda^2)

Could you help me to solve my issue ? 

What am I doing wrong ? Do I have to use another command for this ?

I would like to thank you in advance.

Best regards,

D.L.

I've just upgraded from Maple 15 to Maple 17, and discover that I cannot any longer write curly right braces in math mode. I use an international (Norwegian) keyboard, where curly right braces should be available by Ctrl+Alt+=, but nothing happens when I try to write this. I can work my way around it by using Copy and Paste, but this is inelegant, particularly when I want to demonstrate Maple for my class of 400 students.

Looking at older posts, I found this question, which concerns inline evaluation with international keyboard in Maple 16. Inline evaluation works fine for me, using Ctrl+Shift+=. So was this fixed at the expense of Ctrl+Alt+= ?

Well-known problem is the problem of placing eight shess queens on an 8×8 chessboard so that no two queens attack each other. In this post, we consider the same problem of placing  m  shess queens on an  n×n  chessboard. The problem has a solution if  n>3  and  m<=n .

Work consists of two procedures. The first procedure  Queens  returns the total number of solutions and saves a complete list of all solutions (global variable  S ). The second procedure  QueensPic  shows the user-defined solutions from the list  S  on the board. Formal argument  t  is the number of solutions in each row of the display. The second procedure should be used in the standard interface, rather than in the classic one, since in the latter it may not work properly.

Queens := proc (m::posint, n::posint)

local It, K, l, L, M, P;

global S, p, q;

It := proc (L)

local P, k, i, j;

M := []; k := nops(L[1]);

for i in L do

for j to n do

if convert([seq(j <> i[s, 2], s = 1 .. k)], `and`) and convert([seq(l[k+1]-i[s, 1] <> i[s, 2]-j, s = 1 .. k)], `and`) and convert([seq(l[k+1]-i[s, 1] <> j-i[s, 2], s = 1 .. k)], `and`) then M := [op(M), [op(i), [l[k+1], j]]]

fi;

od; od;

M;

end proc;

K := combinat:-choose([`$`(1 .. n)], m);

S := [];

for l in K do P := [];

L := [seq([[l[1], i]], i = 1 .. n)];

P := [op(P), op((It@@(m-1))(L))];

S := [op(S), op(P)]

od;

p := args[1]; q := args[2];

nops(S);

end proc:

QueensPic := proc (M, t::posint)

local m, n, HL, VL, T, A, N;

uses plottools, plots;

m := p; n := q; N := nops(args[1]);

HL := seq(line([.5, .5+k], [.5+n, .5+k], color = black, thickness = 2), k = 0 .. n);

VL := seq(line([.5+k, .5], [.5+k, .5+n], color = black, thickness = 2), k = 0 .. n);

T := [seq(textplot([seq([op(M[i, j]), Q], j = 1 .. m)], color = red, font = [TIMES, ROMAN, 24]), i = 1 .. N)];

if m <= n and 3 < n then

A := seq(display(HL, VL, T[k], axes = none, scaling = constrained), k = 1 .. N), seq(display(plot([[0, 0]]), axes = none, scaling = constrained), k = 1 .. t*ceil(N/t)-N);

Matrix(ceil(N/t), t, [A]);

display(%);

fi;

end proc:

Examples of work:

Queens(5, 6);  

S[70], S[140], S[210];

QueensPic([%], 3); 

                                                                            248

[[1, 5], [2, 3], [3, 6], [4, 4], [6, 1]], [[1, 3], [2, 5], [4, 1], [5, 4], [6, 2]], [[2, 1], [3, 4], [4, 2], [5, 5], [6, 3]]

Two solutions of classic problem:

Queens(8, 8); 

S[64..65];

QueensPic(%, 2);

                                                                                      92

[[[1, 5], [2, 8], [3, 4], [4, 1], [5, 7], [6, 2], [7, 6], [8, 3]], [[1, 6], [2, 1], [3, 5], [4, 2], [5, 8], [6, 3], [7, 7], [8, 4]]]

Queens_problem.mw

I would like to find the derivative for f(x)=min(x^2 +1, 2x+3) and plot f(x) and its derivative on the same graph. I know the "diff" command works on functions, but I'm not sure how to use it on this one. Suggestions would be appreciated. Thanks!

Fail to do Volume of Revolution when rotate in y-axis by using student calculus 1 packege.

It is good in any x-axis thorugh.

the erorr looks like this, I follow the direction on Maple website and enter axis = vertical, but it give me something like this.

I type vertical := x = 0 somewhere, I was wondering the Maple think vertical = x = 0, so O change the
vertical := x = 0 to v := x = 0(like first image), but after I run the whole thing it still give me same error.

The weirdest part is I actually run the second one scuccess first time, but second time it failed and I don't know why. I input exactly samething but it failed, weird!!

How do you express sin(4x)^2 in terms of powers of cos(x) in Maple 17?

q[1] = sqrt(x)*alpha-lambda(sqrt(x)*alpha-lambda*q[1]*q[3]-p[2])*(sqrt(x)*alpha-lambda*q[1]*q[2]-p[3])-p[1]

I am looking for q[1] solution. When I solve for q[1], maple gives me following answer:

q[1] = RootOf(-_Z+sqrt(x)*alpha-lambda(sqrt(x)*alpha-lambda*_Z*q[3]-p[2])*sqrt(x)*alpha+lambda(sqrt(x)*alpha-lambda*_Z*q[3]-p[2])*lambda*_Z*q[2]+lambda(sqrt(x)*alpha-lambda*_Z*q[3]-p[2])*p[3]-p[1])

Is it possible to obtain a classical solution for the calculations above. (can not understand the meaning of: RootOf and _Z. I need q[1] in order to solve further in my system of eqautions for  q[2],  q[3]

could you help me please to find a solution for this issue...
I would like to thank you in advance 
Best regards,

D.L.

Hi folks,

from an experiment I gathered some data which I am now trying to display in a nice plot. The data contains x and y values (as well as errors for the y values, that are not part of my problem however). It appears that 'ErrorPlot' (Statistics package) seems to be the tool to use in my case, however I am not able to figure out how to assign the x values to the y values. By default Maple uses positive integers as the x values for any input set. Let's say my data is

x:=[1,5,8,9,10,15]

y:=[4,3,2,8,9,9] (with errors yr:=[0.5,0.5,0.5,0.5,0.5,0.5])

then, now matter how I try, the x values assigned are always 1,2,3,.. . Doing sth. like

> ErrorPlot([x,y]);

displays the sets of x and y each being assigned to integers rather than plotting y over x.
Can anybody help me with this issue?

tl;dr

How do I assign individual x values for my set of data using 'ErrorPlot' (from the Statistics pkg)?

Thank you very much!

Greets,
mulo

Hi 

Fairly new to Maple and having trouble with the result displayed when using exponential functions. 

So I have the following function h(r), in which f1 - f5 are unknown constants that are to be calculated. [I am attempting to set up the equations needed to do so]:

h := r → exp(f1 + f2r + f3r² + f4r³ + f5r⁴ + f6r⁵)

Firstly, I need to evaluate h(r) at the point A. But, on entering the evaluate command, the general expression for h is re-produced:

A := 0.2

evalf(h(A)) 

exp(f6r^5+f5r^4+f4r^3+f3r^2+f1+f2r)

Further, I need to take the natural logarithm of h(A), which produces:

evalf(ln(h(A))

ln(exp(f6r^5+f5r^4+f4r^3+f3r^2+f1+f2r))

How do I get Maple to output the actual result of the substitution of r=A and the logarithm?

i.e. how do I get maple to display:

f1 + 0.2f2 + 0.04f3 + 0.008f4 + 0.0016f5 + 0.00032f6

Apologies if this is a very basic question. 

Cheers