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restart;
u := (H(x, t, z)+sqrt(R))*exp(I*R*x);
                /              (1/2)\           
                \H(x, t, z) + R     / exp(I R x)

I*(Diff(u, z))+Diff(u, `$`(x, 2))+Diff(u, `$`(t, 2))+(abs(u)*abs(u))*u-((abs(u)*abs(u))*abs(u)*abs(u))*u;
  / d  //              (1/2)\           \\
I |--- \\H(x, t, z) + R     / exp(I R x)/|
  \ dz                                   /

     / 2                                   \
     |d  //              (1/2)\           \|
   + |-- \\H(x, t, z) + R     / exp(I R x)/|
     \                                     /

     / 2                                   \                    
     |d  //              (1/2)\           \|                  2 
   + |-- \\H(x, t, z) + R     / exp(I R x)/| + (exp(-Im(R x)))  
     \                                     /                    

                       2                                    
  |              (1/2)|  /              (1/2)\              
  |H(x, t, z) + R     |  \H(x, t, z) + R     / exp(I R x) - 

                                        4                       
                 4 |              (1/2)|  /              (1/2)\ 
  (exp(-Im(R x)))  |H(x, t, z) + R     |  \H(x, t, z) + R     / 

  exp(I R x)
value(%);
  / d            \              / d  / d            \\           
I |--- H(x, t, z)| exp(I R x) + |--- |--- H(x, t, z)|| exp(I R x)
  \ dz           /              \ dx \ dx           //           

         / d            \             
   + 2 I |--- H(x, t, z)| R exp(I R x)
         \ dx           /             

     /              (1/2)\  2           
   - \H(x, t, z) + R     / R  exp(I R x)

     / d  / d            \\                             2 
   + |--- |--- H(x, t, z)|| exp(I R x) + (exp(-Im(R x)))  
     \ dt \ dt           //                               

                       2                                    
  |              (1/2)|  /              (1/2)\              
  |H(x, t, z) + R     |  \H(x, t, z) + R     / exp(I R x) - 

                                        4                       
                 4 |              (1/2)|  /              (1/2)\ 
  (exp(-Im(R x)))  |H(x, t, z) + R     |  \H(x, t, z) + R     / 

  exp(I R x)
simplify(%);
  / d            \              / d  / d            \\           
I |--- H(x, t, z)| exp(I R x) + |--- |--- H(x, t, z)|| exp(I R x)
  \ dz           /              \ dx \ dx           //           

         / d            \                 2                      
   + 2 I |--- H(x, t, z)| R exp(I R x) - R  exp(I R x) H(x, t, z)
         \ dx           /                                        

      (5/2)              / d  / d            \\           
   - R      exp(I R x) + |--- |--- H(x, t, z)|| exp(I R x)
                         \ dt \ dt           //           

                                                  2           
                             |              (1/2)|            
   + exp(-2 Im(R x) + I R x) |H(x, t, z) + R     |  H(x, t, z)

                                                  2       
                             |              (1/2)|   (1/2)
   + exp(-2 Im(R x) + I R x) |H(x, t, z) + R     |  R     

                                                  4           
                             |              (1/2)|            
   - exp(-4 Im(R x) + I R x) |H(x, t, z) + R     |  H(x, t, z)

                                                  4       
                             |              (1/2)|   (1/2)
   - exp(-4 Im(R x) + I R x) |H(x, t, z) + R     |  R     
collect(%, exp(I*R*x));
 /  (5/2)       / d            \      2           
 |-R      + 2 I |--- H(x, t, z)| R - R  H(x, t, z)
 \              \ dx           /                  

        / d            \   / d  / d            \\
    + I |--- H(x, t, z)| + |--- |--- H(x, t, z)||
        \ dz           /   \ dx \ dx           //

      / d  / d            \\\           
    + |--- |--- H(x, t, z)||| exp(I R x)
      \ dt \ dt           ///           

                                                   2           
                              |              (1/2)|            
    + exp(-2 Im(R x) + I R x) |H(x, t, z) + R     |  H(x, t, z)

                                                   2       
                              |              (1/2)|   (1/2)
    + exp(-2 Im(R x) + I R x) |H(x, t, z) + R     |  R     

                                                   4           
                              |              (1/2)|            
    - exp(-4 Im(R x) + I R x) |H(x, t, z) + R     |  H(x, t, z)

                                                   4       
                              |              (1/2)|   (1/2)
    - exp(-4 Im(R x) + I R x) |H(x, t, z) + R     |  R     
 

I run Maple 2021 under Ubuntu 20.04 on a new Lenovo laptop with 32Gb of Ram. Every time I start Maple, it runs for a few minutes and then loses the "kernel connection". I have to save the worksheet and re-start Maple. In dmesg, I find:

[ 1436.724570] oom-kill:constraint=CONSTRAINT_NONE,nodemask=(null),cpuset=/,mems_allowed=0,global_oom,task_memcg=/user.slice/user-1000.slice/user@1000.service,task=mserver,pid=8037,uid=1000
[ 1436.724589] Out of memory: Killed process 8037 (mserver) total-vm:31723552kB, anon-rss:31289772kB, file-rss:60kB, shmem-rss:0kB, UID:1000 pgtables:61656kB oom_score_adj:0
[ 1437.151441] oom_reaper: reaped process 8037 (mserver), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB

indicating that Maple's virtual memory exceeded 30 Gb! This happens even if the only command I execute is, for instance, "resrart" or "A:=1" and nothing else. It also happens when no other applications are running and the "top" command indicates that around 30Gb of RAM is available.

In this state, Maple is utterly useless to me. This was a new install of Maple and a fresh install of Ubuntu on a new laptop, surely I am not the only one seeing this?

I have tried setting a 30Gb limit in "kerneloptions" for "stacklimit" but that di not make a difference.

If you have seen any behaviour like this, please respond. Is there some bug in Maple that leads to oncontrolled and unprovoked memory grabbing?

I can export a worksheet (to many different formats), but the normal way of doing this requires a human in the loop and several mouse operations.

Is there a way to automate this?

I have on the order of 100 different worksheets and would like to capture them in an archival format (e.g., PDF).

> with(LinearAlgebra) :
> a:=<<.1,.2>|<.3,.4>>:
> ScalarMultiply(a,.1);

INTEL MKL ERROR: /home/jet08013/maple2022/bin.X86_64_LINUX/libmkl_gf_lp64.so: undefined symbol: mkl_blas_cdgmm_batch_strided.
Intel MKL FATAL ERROR: Cannot load libmkl_gf_lp64.so.
maple: fatal error, lost connection to kernel

This is EXTREMELY inconvenient.

ImportGraph reads one or more graphs from a file. For a file containing multiple graphs, the supported formats are digraph6, graph6, and sparse6. I notice that one option is "output = graph or list, or iterator". However, in my programming with Maple, I was reminded several times that list is only good for a small amount of data.  

Although I can convert the list to an array using the convert function, the time spent in the conversion process needs to be considered.

restart: 
with(GraphTheory):
L:=ImportGraph("C:/Users/eul10c.g6", graph6, output=list):#31026 connected eulerian graphs on 10 vertices graphs and Change to your path here.
convert(L,Array) 

So does it make more sense to provide an "output=Array" as an output option?

eul10c.txt

When resizing a textplot the text is not scaled. 

Hi,

I want to extract the highest linear and non-linear terms in an equation without their coefficients

How I can do it?

For example in the following equation, the highest linear and nonlinear without coefficients are diff(u(T),T$3) and u(T)*diff(u(T),T), respectively.

w*a*diff(u(T),T)+a*u(T)*diff(u(T),T)-(b^2)*a*w*diff(u(T),T$3)=0

Thanks in advance.

Maple 2022:

It appears that one can use push_back() with an empty DEQueue(), but not push_front().

Since the queue is double-ended and empty, this doesn't make much sense to me. So should this be considered a "bug"?

See the attached

  restart:

#
# This works
#
  A:=DEQueue();
  empty(A);  
  push_back(A,2);
  

module DEQueue () local num, head, tail, storage, dsp; option object; end module

 

true

 

module DEQueue () local num, head, tail, storage, dsp; option object; end module

(1)

#
# But this results in an error!
#
  B:=DEQueue();
  empty(B);
  push_front(B,2);

module DEQueue () local num, head, tail, storage, dsp; option object; end module

 

true

 

Error, invalid return value from method moduledefinition: 'NULL'

 

 

Download DEQueue_Prob.mw

A question by @Shameera  I was working on has disapeared meanwhile.
It was related to this previous thread 233822-How--To-Solve-This-Equation-By-Using but has not been displaced in it.
Did a regolaror do this or was it  @Shameera ?

I have seen that this is possible (for example in the example:  2-D Flexible Spin-up Beam).

When I copy an image to the Windows10 clipboard it does paste to other applications but not to MapleSim. Instead, I get an audio notification from the system that is played on other instances when an action cannot be performed.

Within MapleSim copy and paste works (also between models). However, copying an image from a Maplesim Model to another Windows App does not work.

Can someone confirm that pasting images works in recent verions?

(Clearing the Clipboard removes images copied with MapleSim.

Observed on 2 Windows 10 installations with the version 2022 and 2021.)

function is F(x)= x-tanh(4*x/T) and diff(F(x))= 1-(4/T)*(1/T*Cosh(4*x/T)^2). x and t variable T max value=7, i want to do plots ising models function. Anyone can help me?

Graphich will be this 

https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcTSo2BHyF5fvb8Dy6bWhELRAAIoaWmxp89G3w&usqp=CAU

macOS 12.3 + Maple 2021.2

* select a region on a document
* context click
* --> Copy as image

Copy as image does not put an image on the clipboard.

What is solution?

Hi
One or two days ago, there was a question here by @nm about an integral that was resulting in an infinite loop. I don't know if this question was accidentally deleted, but I don't see it anymore.

The question was about the computation of 

> integrand := (a + b*(c*x^n)^(1/n))^p/x;
> int(integrated, x);

Indeed, there was a problem in the routines to derive assumptions, surfacing as the problem in int pointed out by @nm . Thanks to Austin Roche ( @aroche ) for his quick fix; the fix is distributed to everybody using Maple 2022 in the Maplesoft Physics Updates v.1184.

Edgardo S. Cheb-Terrab
Physics, Differential Equations and Mathematical Functions, Maplesoft

I knew it can't be true that timelimit in Maple 2022 no longer hangs and it is only a matter of time before I find a case where it still hangs.

Here are examples. timelimit hangs. No error or anything, it just hangs. timelimit is just ignored. set the limit to 60 seconds  (CPU time), and waited for 20 minutes (real time) and nothing happend.

I hope in Maple 2023 this will be fixed. Could others confirm this? it only hangs when adding the method=_RETURNVERBOSE otherwise it does not hang.

interface(version);

`Standard Worksheet Interface, Maple 2022.0, Windows 10, March 8 2022 Build ID 1599809`

Examples of timelimit hangs in Maple 2022

 

Example 1

restart;

integrand:=(B*x+A)/(c*x^2+b*x+a)^2/(f*x^2+e*x+d)

try
  timelimit(60,int(integrand,x,method=_RETURNVERBOSE));
catch:
  print("Timed out");
end try;

 

Example 2

restart

integrand:=(5*x^4-x^3+3*x^2+x+2)*(2*x^2-x+3)^(1/2)/(5+2*x)^3

try
    timelimit(60,int(integrand,x,method = _RETURNVERBOSE));
catch:
  print("Timed out");
end try;

 

 

Download int_hangs.mw

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