Maple 2015 Questions and Posts

These are Posts and Questions associated with the product, Maple 2015

nullspace or reducedform or Eigenvectors still can not find eigenvector in terms of  mmm , how to find this?

 

mmm is a variable

 in eigenvector using nullspace and eigenvector using maple function  Eigenvectors ? 

I'm reading a string from a textbox, and I need to know where the line breaks are. Hint:They are not found by searching for \n.

I am (again) trying to get Maple to do some parallel work; using the Threads package.

My actual problem involves a vector function with 6 elements, acting on 6-vectors. Each element of the output vector is calculated as a high-order polynomial of all 6 input elements. The whole thing is a map that I want to iterate. I plan to evaluate each of the 6 functions in a separate thread (the input vector of course is the same for all six) and then put the results together in a Vector, to be used as input for the next iteration.

Facing difficulty I finally wrote myself a little toy program to check out the basic mechanism. Here it is:

restart;
                "Maple Initialization loaded..."
with(Threads):
f:=x -> 1+x^2;
                                       2
                        f := x -> 1 + x
x:=0:
tt:=time[real]():

for i from 1 to 10 do
  id:=Create(f(x),y):
  Wait(id):
  x:=y:
  y:='y':
end do:

time[real]()-tt;
                             0.018
i;
                               11
So far so good; even the output (not shown) makes sense. BUT: as I increase the number of iterations in the for...do loop, the memory allocation goes up fast, and I hit a point at about 40 iterations where the whole process locks up and the program never ends, cannot even be stopped (at least for 100 iterations), forcing me to abort the whole thing. I have evidence that Maple allocates vast amounts of memory which finally chokes the whole thing (on a 16 GB-RAM machine).

Anyone have any idea what I am doing wrong? I realize the above example does not provide benefits; in the real example there will be 6 Creates and the loop will Wait for all of these to finish.

I'd really like to get this to work as each function can take quite some time and I do expect at least some speed-up from parallelizing this (even after overhead).

This is on Maple 2015 on Mac OS X 10.10.5 with 16 GB of RAM. I should mention that I set UseHardwareFlots:=true in my .mapleinit file.

Thanks,

M.D.

H2 := [a(t)*(diff(c(t), t))+b(t) = 100, a(t)*(diff(b(t), t))+c(t)*(diff(b(t), t)) = exp(t), a(t)*(diff(c(t), t))+a(t)*(diff(b(t), t))+b(t) = 90];
H1 := subs([diff(a(t),t)=a1,diff(b(t),t)=b1,diff(c(t),t)=c1], H2);
H := subs([a(t)=a0, b(t)=b0, c(t)=c0], H1);
ics := generate_ic(H, {a0=-2..2, b0=-2..2, c0=-2..2,a1 = -2 .. 2, b1 = -2 .. 2, c1 = -2 .. 2, t = 0, energy = 0}, 100);

 

Error, (in generate_ic) invalid input: `DEtools/generate_ic` expects its 1st argument, H, to be of type algebraic, but received [a0*c1+b0 = 100, a0*b1+c0*b1 = exp(t), a0*c1+a0*b1+b0 = 90]

Hi,

I would like to plot a cone where I can change the vertex angle directly. I would also to be able to change the size of the cone. I have tried:

cone([r*cos(phi)*sin(theta), r*sin(phi)*sin(theta), r*cos(theta)], phi = 0 .. 2*Pi, r = 0 .. 1, theta = (1/6)*Pi, coords = spherical)

but this gives me the following error:

Error, (in plot3d) unexpected options: [[r*cos(phi)*sin(theta), r*sin(phi)*sin(theta), r*cos(theta)], phi = 0 .. 2*Pi, r = 0 .. 1, theta = (1/6)*Pi]

Thanks!

with(DEtools):
phaseportrait([secret], [a(t), b(t), c(t)], t = -2 .. 2, [[a(0) = 1, b(0) = 0, c(0) = 2]], stepsize = 0.5e-1, scene = [c(t), a(t)], linecolour = sin((1/2)*t*Pi), method = classical[foreuler]);

Error, (in DEtools/phaseportrait) the ODE system does not contain derivatives of the unknown function a

Environment: Maple2015, MATLAB_R2014b(MacOSX10.8.5), 2015b(MacOSX10.11.4)

MapleToolbox2015.1MacInstaller.app was successfully completed (log tells us), but when MATLAB were booted, following error messages appeared and symbolic operations of maple failed. 

This would be closely related to maple installation on MATLAB as such errors never occur for clean install of MATLABs and looks independent on OSX versions. Now javaforosx.dmg in use by instruction of Maplesoft.  Something wrong is in Maple2015. Note maple-MATLAB link works normally.

Please provide us with direction of how to fix it hopefully by Maplesoft professionals.

 

(Quote of MATLAB command window display)

Exception in thread "Startup Class Loader" java.lang.UnsatisfiedLinkError: jogamp.common.os.MachineDescriptionRuntime.getPointerSizeInBytesImpl()I

at jogamp.common.os.MachineDescriptionRuntime.getPointerSizeInBytesImpl(Native Method)

at jogamp.common.os.MachineDescriptionRuntime.getRuntimeImpl(MachineDescriptionRuntime.java:138)

at jogamp.common.os.MachineDescriptionRuntime.getRuntime(MachineDescriptionRuntime.java:124)

at com.jogamp.common.os.Platform.<clinit>(Platform.java:228)

at javax.media.opengl.GLProfile.<clinit>(GLProfile.java:83)

at com.mathworks.hg.peer.JavaSceneServerPeer.initializeJOGL(JavaSceneServerPeer.java:114)

at com.mathworks.hg.peer.JavaSceneServerPeer.<clinit>(JavaSceneServerPeer.java:100)

at java.lang.Class.forName0(Native Method)

at java.lang.Class.forName(Class.java:190)

at com.mathworks.mde.desk.StartupClassLoader.loadClass(StartupClassLoader.java:258)

at com.mathworks.mde.desk.StartupClassLoader.access$900(StartupClassLoader.java:25)

at com.mathworks.mde.desk.StartupClassLoader$2.run(StartupClassLoader.java:244)

at java.lang.Thread.run(Thread.java:745)

>> maple();

error: maple (line 178)

Invalid MEX-file '/Applications/MATLAB_R2014b.app/toolbox/maple/maplemex.mexmaci64':

dlopen(/Applications/MATLAB_R2014b.app/toolbox/maple/maplemex.mexmaci64, 6): Symbol not found: ___sincos_stret

  Referenced from: /Library/Frameworks/Maple.framework/Versions/2015/bin.APPLE_UNIVERSAL_OSX/libhf.dylib

  Expected in: /usr/lib/libSystem.B.dylib

 in /Library/Frameworks/Maple.framework/Versions/2015/bin.APPLE_UNIVERSAL_OSX/libhf.dylib

>> syms x  y

error: sym (line 186)

Invalid MEX-file '/Applications/MATLAB_R2014b.app/toolbox/maple/maplemex.mexmaci64':

dlopen(/Applications/MATLAB_R2014b.app/toolbox/maple/maplemex.mexmaci64, 6): Symbol not found: ___sincos_stret

  Referenced from: /Library/Frameworks/Maple.framework/Versions/2015/bin.APPLE_UNIVERSAL_OSX/libhf.dylib

  Expected in: /usr/lib/libSystem.B.dylib

 in /Library/Frameworks/Maple.framework/Versions/2015/bin.APPLE_UNIVERSAL_OSX/libhf.dylib

 error: sym (line 56)

           assignin('caller',varargin{i},sym(varargin{i})); 

(Unquote)

 

 

 

Hello..  I want to know if there is anny command to show the matrix of linear system.  I recently entred a 64 equations and i solved it by command solve,  but i want to show the matrix of system..  So plz. Help 

I've got the following:

Integral_over_region.mw

M_Iwaniuk

 

hi .why matrix a dont create?

bot.mw

psi := (1/4)*(1-Zeta)^2*(2+Zeta), (1/4)*(1-Zeta)^2*(Zeta+1), (1/4)*(Zeta+1)^2*(2+Zeta), (1/4)*(Zeta+1)^2*(Zeta-1)

(1/4)*(1-Zeta)^2*(2+Zeta), (1/4)*(1-Zeta)^2*(Zeta+1), (1/4)*(Zeta+1)^2*(2+Zeta), (1/4)*(Zeta+1)^2*(Zeta-1)

(1)

psi[1]

(1/4)*(1-Zeta)^2*(2+Zeta)

(2)

for i to 4 do for j to 4 do a[i, g] = 2*psi[i]*psi[j] end do end do

a

a

(3)

`a__1,1`

`a__1,1`

(4)

NULL

 

Download bot.mw

I have downloaded and trying to run the application "Traveling Salesman Problem" by Bruno Guerrieri: 

http://www.maplesoft.com/applications/view.aspx?SID=6873

However, the animations do not work properly. Instead of the animations, I get series of sets of plots. Each such set consists of four plots: one with a green edge, one with a blue edge, one with blue edges, and one with points (nodes).

I guess, it happens because of a new version of maple: the application was created in 2008 for Maple 12, and I use Maple 2015.

Could anybody, please, tell me what exactly should I change in the code so that it will work properly?

Any help will be very much appreciated.

Many thanks in advance!

This is for the infamous Calc 2 Goblet Maple Project

I have tried everything changed all the numbers and got nowhere or worse results. The only thing that accurately works is the example project:

(0, 1.5) and end at (0.5, 0.2). which equals f1(x)=-2.6x+1.5

and f2:=x->0.2+0.05*sin(2*(x-0.5)) which is really 0.2+0.05sin(2x-1)

The goal is to change the example project so it becomes something of my own creation. 

When I change f2:=x->0.4+0.05*sin(2*x-0.5)) it is at least attached but forms a sharp dip down first then connects at the point when it should be smooth curve. It seems you can do anything to the other curve

f3:=x->a*x^3+b*x^2+c*x+d;
x -> a x^3 + b x^2 + c x + d

connection1:=f3(5.5)=f2(5.5);
166.375 a + 30.25 b + 5.5 c + d = 0.3727989445

arc1:=f3(7)=1;
343 a + 49 b + 7 c + d = 1

arc2:=f3(7.5)=0.9;
421.875 a + 56.25 b + 7.5 c + d = 0.9

arc3:=f3(9)=1.6;
729 a + 81 b + 9 c + d = 1.6

values:=solve({eq1,eq2,eq3,eq4},{a,b,c,d});

F:=x->piecewise(x<0.5,f1(x),x>=0.5 and x<5.5,f2(x),x>=5.5,f3(x));

plot(F(x),x=0..9,y=0..4,scaling=constrained);

So how can this be fixed?

I need to do this with a sequence of a large number of elements but here is my question with a sequence of fewer elements.

a:={10,11,-13,9,20,74,10}:

I want to check each element of the sequence if it is negative. And if any element is negative I want to replace with 0 (or do something else). I tried the following code but it didn't work. 

for k from 1 to 7 do
  if (a[k]<0) then subs(a[k]=0, a) end if:
end do;

Please help me to figure it out. 

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