Code was computed on two different PC:
1) Win 8.1, Maple 17.02 x64
2) Win 8.1, Maple 18.01 x64

In brief:

n:=3: 
Grid:-Seq('f(i)', i = 1 .. n): 

works well in Maple 17.02 but gives an error in Maple 18.01. Why?

However,

(j -> Grid:-Seq('f(i)', i = 1 .. j))(n):

works well for both Maple versions.

according to examples from Maple help page
http://www.maplesoft.com/support/help/Maple/view.aspx?path=Grid%2fSeq
we have to pass exactly 'f(i)' (not just f(i)) into Grid:-Seq(...). Why?

Why doesn't Digits:=30: work properly for Grid:-Seq(...)?

For details see attached file. Output was produced in Maple 17.02. In Maple 18.01 the output will differ.

Download Grid[Seq].mw

I want to solve the equation sqrt(x) + sqrt(1 - x^2) = sqrt(2 - 3*x - 4*x^2) in RealDomain. I tried

RealDomain:-solve(sqrt(x) + sqrt(1 - x^2) = sqrt(2 - 3*x - 4*x^2),x);

And I got one solution. But, at here 

At here http://mathematica.stackexchange.com/questions/51316/how-can-i-get-the-exact-real-solution-of-this-equation 

they said the given equation has two real solutions. How must I understand?

I am not able to simplify my equation, any help would be appreciated ! I want the  term to be eliminated

Download 1.mw

Hi Mapleprimers,

I was wondering if there way a way to use restart(); and clear Maple's memory, but protect the memory in a certain variable?  I would like to return the memory to the operating system, but keep a symholic function in memory.

Alternatively, is there a way to save a symbolic function to a file, then reload it at a seperate time?

Hi MaplePrime-ers,

I'm using Maple17 in Matlab 2012b to evaluate a symbolic function over a grid of values.  The number of values is generally ~500k, and therefore I have a loop that dumps the solutions into MATLAB where the values are parsed and stored more efficiently.

I put this proceess in an optimization routine, and I keep getting crashes.  The crashes are NOT repeatable.  They generally happen after 4-10 times the routine has been called.  

This is one of the stack dumps.  Anybody have any ideas?  I talked to MATLAB support, but they weren't very useful (they started pointing fingers).

------------------------------------------------------------------------
Segmentation violation detected at Wed Jun 4 17:38:11 2014
------------------------------------------------------------------------

Configuration:
Crash Decoding : Disabled
Current Visual : 0x24 (class 4, depth 24)
Default Encoding: UTF-8
GNU C Library : 2.15 stable
MATLAB Root : /opt/Matlab/R2012b
MATLAB Version : 8.0.0.783 (R2012b)
Operating System: Linux 3.2.0-37-generic #58-Ubuntu SMP Thu Jan 24 15:28:10 UTC 2013 x86_64
Processor ID : x86 Family 6 Model 23 Stepping 6, GenuineIntel
Virtual Machine : Java 1.6.0_17-b04 with Sun Microsystems Inc. Java HotSpot(TM) 64-Bit Server VM mixed mode
Window System : The XFree86 Project, Inc (40300000), display wildnode0:15.0

Fault Count: 1

Abnormal termination:
Segmentation violation

Register State (from fault):
RAX = 00007f3bcc0a80c0 RBX = 00007f3b97fe6000
RCX = 0000000000000000 RDX = 00007f3bcc0a84a0
RSP = 00007f3b8cb29d60 RBP = 0000000000000003
RSI = 5851f42d4c957f2d RDI = 00007f3bde026360

R8 = 65a1566174cc9e28 R9 = 0000000000000002
R10 = 00007f3b8cb29d90 R11 = 0000000000002e88
R12 = 0000000000000001 R13 = 00007f3b8cb29df0
R14 = 0000000000000000 R15 = 0000000000000003

RIP = 00007f3b977d0604 EFL = 0000000000010283

CS = 0033 FS = 0000 GS = 0000

Stack Trace (from fault):
[ 0] 0x00007f3c962b01de /opt/Matlab/R2012b/bin/glnxa64/libmwfl.so+00516574 _ZN2fl4diag15stacktrace_base7captureERKNS0_14thread_contextEm+000158
[ 1] 0x00007f3c962b14b2 /opt/Matlab/R2012b/bin/glnxa64/libmwfl.so+00521394
[ 2] 0x00007f3c962b2ffe /opt/Matlab/R2012b/bin/glnxa64/libmwfl.so+00528382 _ZN2fl4diag13terminate_logEPKcRKNS0_14thread_contextE+000174
[ 3] 0x00007f3c9559f093 /opt/Matlab/R2012b/bin/glnxa64/libmwmcr.so+00557203 _ZN2fl4diag13terminate_logEPKcPK8ucontext+000067
[ 4] 0x00007f3c9559bb9d /opt/Matlab/R2012b/bin/glnxa64/libmwmcr.so+00543645
[ 5] 0x00007f3c9559d835 /opt/Matlab/R2012b/bin/glnxa64/libmwmcr.so+00550965
[ 6] 0x00007f3c9559da55 /opt/Matlab/R2012b/bin/glnxa64/libmwmcr.so+00551509
[ 7] 0x00007f3c9559e0fe /opt/Matlab/R2012b/bin/glnxa64/libmwmcr.so+00553214
[ 8] 0x00007f3c9559e295 /opt/Matlab/R2012b/bin/glnxa64/libmwmcr.so+00553621
[ 9] 0x00007f3c93a86cb0 /lib/x86_64-linux-gnu/libpthread.so.0+00064688
[ 10] 0x00007f3b977d0604 /opt/maple17/bin.X86_64_LINUX/libmaple.so+01824260
[ 11] 0x00007f3b977cfc48 /opt/maple17/bin.X86_64_LINUX/libmaple.so+01821768
[ 12] 0x00007f3b977d2f88 /opt/maple17/bin.X86_64_LINUX/libmaple.so+01834888
[ 13] 0x00007f3b9763d63f /opt/maple17/bin.X86_64_LINUX/libmaple.so+00173631
[ 14] 0x00007f3c93a7ee9a /lib/x86_64-linux-gnu/libpthread.so.0+00032410
[ 15] 0x00007f3c937ab3fd /lib/x86_64-linux-gnu/libc.so.6+01000445 clone+000109

If this problem is reproducible, please submit a Service Request via:
http://www.mathworks.com/support/contact_us/

A technical support engineer might contact you with further information.

Thank you for your help.

I want to do a step by step computation for obtaining the coefficents of the sine fourier series expansion of f(x)=x over the interval [-L,L]. The steps are as follows:

1-write the fourier expansion as: Sum(A[n]*sin(n*pi*x/L),n=1..N)
2-multiply the series by: sin(m*pi*x/L)
3-integrate the series over the interval [-L,L]
3-using the orthogonality properties of the set {sin(n*pi*x/L} compute the A[n].

I can't do these steps since I have problem with the series manipulations in maple!
Can any one suggest a way from begining to the end?

Thanks. :)
Below shows what I did in Maple 17.

Hi MaplePrimers,

I've written a function that needs to be evaluated at a bunch of different points.  Evaluating it in a loop works. I'm wondering if there was a faster way to do this because I'm evaluating a list of 400k+ sets of points.  

Right now I'm using a loop with the following code.

for i from 1 to 500000 do 
     Results(i):= f(L[i][])[1];
od;

 

If I have a function f, which has 5 arguements, f(y, w, x,y,z).

I also have a list of those arguements:  L = [[1,2,3,2,3],[4,5,6,2,3],[7,8,9,2,3]]

What would be the fastest way to get a list of results?  Also, is there a way that I could preallocate memory for this list?

Ideally, I would like to get the output as as list.  ie:

Results:= [[f(1,2,3,2,3)], [f(4,5,6,2,3)], [f(7,8,9,2,3)]]

Hi,

I have a file with arbitrary points which I want to connect with a surface. I have seen similar problems on this site but I can't fix my problem with the answers that are given, mainly because my points are just plain vectors. Can anybody help me? 
These are my points/vectors:

v1 := `<,>`(15, 6, 14.89);
v2 := `<,>`(15, 8, 14.72);
v3 := `<,>`(15, 10, 14.79);
v4 := `<,>`(15, 12, 14.95);
v5 := `<,>`(15, 14, 15.17);
v6 := `<,>`(15, 16, 15.43);
w1 := `<,>`(15/2, 4, 9.78);
w2 := `<,>`(15/2, 6, 9.95);
w3 := `<,>`(15/2, 8, 9.85); 
x1 := `<,>`(15*(1/3), 4, 8.71);
x2 := `<,>`(15*(1/3), 6, 8.44);
y1 := `<,>`(15/4, 4, 8.31); 

I can only plot the different points with 

with(plots);
pointplot3d({v1, v2, v3, v4, v5, v6, w1, w2, w3, x1, x2, y1}, scaling = CONSTRAINED, symbolsize = 20, color = red, axes = normal, labels = ["L/h", "n", "kg/m"]);

I hope someone can help me!

Good day, please how can one solve these BVPs using FINITE DIFFERENCE METHOD in maple. Here is the problem FDM.mw

Hello

I have a nasty expression which I want to simplify in terms of another expression/function I have defined. 

Please can you tell me how to do this?

A simple example would be:

myFunction := a^2 + b^2

horribleFunction:= a^2 + b^2 + ...

I want it to simplify so I get something like

A(myFunction)^n  + .....

Above is just a simplifcation to try and explain what I mean

Thanks

I'm trying to use Rodrigues' Rotation Formula to graph a circle--by rotating a point, naturally--and I'm not sure how to implement that in Maple. For something like a function, allowing a variable--say, x--to vary and produce a curve is natural, but the evalm() function doesn't handle that very well: I can use the formula to *evaluate* the rotations, but not to use them to graph the circle.

I looked for something like solids of revolution--after all, I'm doing something pretty similar--but didn't find anything helpful; apparently there's a way to make solids of revolution, but it's pretty specific and would be difficult to adapt?

I am having an issue with Physics[Vectors] in Maple 17, specifically an interference with PDEtools:-dchange. My apologies, this post is lengthy & a bit messy. I did upload a worksheet with the code; link at the end. The upload exhibits the UNWANTED behaviour in Maple 17.

Here are a few lines of code that exhibit the WANTED behaviour (change of variable and solving a de). it is run in Maple17 with Physics loaded but NOT Physics[Vectors]. The paste into Mapleprimes looks too messy to be useful so I am just showing the relevant lines; the file has everything:

-(diff(E1_(x, y, z, t), x, x))-(diff(E1_(x, y, z, t), y, y))-(diff(E1_(x, y, z, t), z, z)) = -mu*epsilon*(diff(E1_(x, y, z, t), t, t));

PDEtools:-dchange({x = r*cos(theta), z = r*sin(theta)}, -(diff(diff(E1_(x, y, z, t), x), x))-(diff(diff(E1_(x, y, z, t), y), y))-(diff(diff(E1_(x, y, z, t), z), z)) = -mu*epsilon*(diff(diff(E1_(x, y, z, t), t), t)), simplify);

subs(E1_(r, theta, y, t) = R(r)*exp(I*(-k*y+omega*t)), -((diff(diff(E1_(r, theta, y, t), y), y))*r^2+(diff(diff(E1_(r, theta, y, t), r), r))*r^2+(diff(E1_(r, theta, y, t), r))*r+diff(diff(E1_(r, theta, y, t), theta), theta))/r^2 = -mu*epsilon*(diff(diff(E1_(r, theta, y, t), t), t)));

dsolve((5));

So far this is all as expected.

Now I rerun this thing with Physics[Vectors] loaded rather than just Physics. Everything looks the same until I get to the line starting with subs(E1_ :

subs(E1_(r, theta, y, t) = R(r)*exp(I*(-k*y+omega*t)), -((diff(diff(E1_(r, theta, y, t), y), y))*r^2+(diff(diff(E1_(r, theta, y, t), r), r))*r^2+(diff(E1_(r, theta, y, t), r))*r+diff(diff(E1_(r, theta, y, t), theta), theta))/r^2 = -mu*epsilon*(diff(diff(E1_(r, theta, y, t), t), t)));

plus many more lines of expressions. I am not sure what is going wrong; but after the dchange the code behaves funky: I have had simplify producing similarly weird expressions etc.

Note that on Maple 15 this all works as expected and no issues show up for me. If the version of Physics I have on Maple 17.02 is bad; how do I change that? (I have not tried to update Physics separately, and it isn't obvious to me where to find it for Maple 17). It is sort-of an issue as I want to use this as a demo for students, who in fact will be running Maple 18... but I am stuck at 17 (and often using 15 at home) so I need this to work there (17), too.

TIA,

Mac Dude

dchangeTest.mw

Hi,

I have written a for-end loop and put all the outcomes of the loop in a matrix and now I want to plot these results but for some reason maple won't plot the matrix in a correct way. If I copy-paste the matrix into an new file maple plots it correct. What is the reason that maple won't plot it in my original file?

Here is my file. 

restart;
Parameters
L := 20; Q := 20; n := 8; h := 3; EAv := 1;
Mat := Matrix(10, 2, storage = sparse);
a := 1;
loop L1
for L1 from .6 by .1 to 1.5 do
L1 := L1;
L2 := 2*L1;
L3 := 1.6*L2;
L4 := (1/2)*L-L1-L2-L3;
alfa1 := evalf(arctan(h/L1));
alfa2 := evalf(arctan(h/L2));
alfa3 := evalf(arctan(h/L3));
alfa4 := evalf(arctan(h/L4));
F4 := (1/2)*Q*L4;
F3 := (1/2)*Q*L3+(1/2)*Q*L4+F4;
F2 := (1/2)*Q*L2+(1/2)*Q*L3+F3;
F1 := (1/2)*Q*L1+(1/2)*Q*L2+F2;
w1 := evalf((1+sin(alfa1)^3)*F1*L1/(EAv*sin(alfa1)^2*cos(alfa1)));
w2 := evalf((1+sin(alfa2)^3)*F2*L2/(EAv*sin(alfa2)^2*cos(alfa2)));
w3 := evalf((1+sin(alfa3)^3)*F3*L3/(EAv*sin(alfa3)^2*cos(alfa3)));
w4 := evalf((1+sin(alfa4)^3)*F4*L4/(EAv*sin(alfa4)^2*cos(alfa4)));
kkm := (w1-w2)^2+(w2-w3)^2+(w3-w4)^2; Mat(a, 1) := L1;
Mat(a, 2) := kkm;
a := a+1
end do;

with(plots);
pointplot(Mat);

Hi,

I have this set of equations but maple won't solve the three variables and it gives an 

Error, (in solve) cannot solve for an unknown function with other operations in its arguments. This are the equations with unknowns, alfa1, alfa2, and alfa3.

eq1 := 3*(1+sin(alfa1)^3)(30/tan(alfa1)+60/tan(alfa2)+60/tan(alfa3))/(sin(alfa1)^2*cos(alfa1)*tan(alfa1)) = 3*(1+sin(alfa2)^3)(30/tan(alfa2)+60/tan(alfa3))/(sin(alfa2)^2*cos(alfa2)*tan(alfa2));

eq2 := 3*(1+sin(alfa1)^3)(30/tan(alfa1)+60/tan(alfa2)+60/tan(alfa3))/(sin(alfa1)^2*cos(alfa1)*tan(alfa1)) = (90*(1+sin(alfa3)^3))/(sin(alfa3)^2*cos(alfa3)*tan(alfa3));

eq3 := 3/tan(alfa1)+3/tan(alfa2)+3/tan(alfa3) = 25/2;

solutions := [solve({eq1, eq2, eq3, alfa1 > 0, alfa2 > 0, alfa3 > 0}, {alfa1, alfa2, alfa3})];

Can anyone help?

So if you are given a 3x3 matrix i was just wondering how to use plot3d and plot the 3 column vectors given by it?  Thanks.