Hello.

I was wondering if it was possible for maple to automatically type in the values of the variables when calculating like

U:=50V

R:=10ohm

U/R=50V/10ohm=5A

instead of just typing

U/R=5A

hope my question makes sense :D

Let x, y, z be nonnegative real numbers. Obviously, x³+y³+z³-4xyz is not always nonnegative, since its value is -1 when x=y=z=1. But why Maple's minimize gives wrong result? 

minimize(x^3 + y^3 + z^3 - 4*x*y*z, x = 0 .. infinity, y = 0 .. infinity, z = 0 .. infinity);

Attachment: MinValue.mws.

MMA's Minimize finds correct infimum: 
So, can Maple always find correct exact (i.e., not just numerical) global minima (or maxima) at least for such problems with a small number of variables as well?

Wanted to plot a vector with the arrow function

for some reason the arrow head was not created. tried changing the input so the resulting coordinat would be [10,10] insted of [725,350] this created an arrowhead on the line.

with(plots):
with(plottools):
l1 := arrow([0, 0], [725, 350], 0.1, 0.4, 0.1, arrow, color = red, legend = "Vector v");
display(l1, axes = frame, view = [0 .. 900, 0 .. 500]);

Why does it not create the arrow head happen???

Either I am clueless (or very tired) or StringTools:-Remove is not behaving as it should (document attached)

IsThisABug.mw

I would like to be able to use python's matplotlib from Maple. I am doing the following currently

with(Python)
Start('home' = "/opt/anaconda3/lib/python3.9", 'path' = "/opt/anaconda3/lib/python3.9/site-packages")
ImportModule("matplotlib as mpl")

and the error I get back is

Error, (in Python:-ImportModule) ModuleNotFoundError: No module named 'matplotlib'
['Traceback (most recent call last):\n', '  File "<string>", line 1, in <module>\n', "ModuleNotFoundError: No module named 'matplotlib'\n"]

The string I passed into path is the directory where matplotlib seems to be located as far as I can tell. I looked this up in my IDE Spyder, but using the command print(matplotlib__file__).

UPDATE: but actually if I open a new worksheet and execute 

with(Python)
Start('home' = "/opt/anaconda3/lib/python3.9", 'path' = "/opt/anaconda3/lib/python3.9/site-packages")

The error is that 

Error, (in Python:-Start) unable to start Python: could not create process, mpython

So Maple isn't finding Python apparently.

I tried for 'home' also "/opt/anaconda3/bin", did not work.
 

In 1D worksheet mode I can't figure out how to insert a line between a and c. 

restart

a:=1
                             a := 1

c:=3
                             c := 3

Hello, everyone. I have plotted a simple equation and now have the following observation regarding it.

1- How to change or control axis style mean style like bold, colour change etc?

2-  How to change or control the font, colour and style of numbers written automatically by maple while plotting on the axis (x-axis, y-axis)?

3- How to change the font, style and colours of labels?

The problem I am facing is that whenever I save or import any graph as png or jpeg and then paste it into MS word, it's quality or pixel changes and it looks very bad. is there any way to save and paste good-quality pictures into documents that means DPI?

Qaulity_Help.mw

I've been running some animations on a Macbook Pro 2015 8GB RAM and a Macbook Pro SIlicon 2021 16GB RAM. The problem I was trying to solve was making these laptops run out of memory (animation of a 3D trajectory with 100000 points).

So I switched to a desktop linux setup with 256GB of RAM and 16 cores. I installed Maple and set everything up but it seems SUPER buggy (menus disappearing when I try to hover over their items) and it just crashes on versions of the problem I have that are easy to run even on the 8GB RAM Macbook from 2015.

Is there a history of the Linux version being worse than the Mac version or something? Is there any chance an .mla file I created on a Mac somehow doesn't work correct on Linux? Could it be some internal Maple limitation on memory? I am wondering what it could be.

The OS is Ubuntu 22.10 and the architecture is x86-64.

The requirements say Ubuntu 21.10. Does this mean at least 21.10, or exactly 21.10?

Maple is 2022.2.

Maple Build Number is 1657361

The freezing/crashing of Maple seems to occur when I play an animation. Everything gets slow and then everything stops working. 1000 point trajectory on a sphere. No issue on a much less powerful Macbook.

Here is a worksheet with the calculations I describe below: subintomatrix.mw

I have a simple three dimensional linear system and I want Maple to solve it for me. 

Using LinearAlgebra:-LinearSolve, the solution is the parametrized Vector (t,-2t,t), which I save to a variable solution.

I'd like to be able to substitute a value into t.

eval(solution, {t=1}) does not work, unfortunately.

I open the command-line of maple 2022, and I can run the code alone. But when I save it in a text named ``6conn.txt", I don't know how to run it.

with(GraphTheory):
g:=Graph({{0 ,1},{3 ,4},{4 ,1},{1 ,3},{3 ,0},{0 ,4},
{2 ,1},{4 ,5},{4 ,2},{3 ,6},{4 ,6},{6 ,5},{1 ,6},{6 ,2},
{5 ,0},{0 ,2},{2 ,5},{7 ,8},{12 ,10},{10 ,11},{11 ,8},{8 ,10},
{10 ,7},{7 ,11},{9 ,8},{11 ,12},{11 ,9},{10 ,13},
{11 ,13},{13 ,12},{8 ,13},{13 ,9},{12 ,7},{7 ,9},{9 ,12},
{8 ,2},{13 ,0},{10 ,5},{12 ,3},{1 ,9},{7 ,6}
});

I tried  .\E:\\6conn.txt or !E:\\6conn.txt. Neither seems to work.

6conn.txt

I have plotted in the same display a pointplot and a constant (a horizontal line)..

The worksheet is:

How do I solve for when the constant plot2 is less than plot1? I know at r=323 it goes above the threshold, but I don't know how to show this in an expression in Maple, and I've looked for several hours now, both Google search and on Maplesoft with no luck.

If I type seq(i,i=1..1000) <enter> I get a large output.

Then when I type

for i from 1 to 5 do
  i;
end do;

It takes Maple 8 seconds to complete the job.  Is this normal when using Windows 7?

It is easy to simplify the following expression (to 4), but maple's ceil function does not seem to be interested in simplifying it.

where n is greater than or equal to 4. 

simplify(ceil((3*n-8)/(n-3))) assuming n>=4, n::positive # As-is output

We have to rewrite "(3*n-8)/(n-3)" in this form "3 + 1/(n - 3)" to recognize.

simplify(ceil(3 + 1/(n - 3))) assuming  n>=4, n::positive

4

• My first question is: How to transform (3*n-8)/(n-3) into 3 + 1/(n - 3) by maple?
• My second question: Can we see the steps of execution of the simplification involving  ceil)?

Don't know if this is a bug or just another proof of my incompetence, but I am struggling in storing values between sessions using DataTable components.

The problem seems to me to be related to nested tables, somehow.

I've made a little example showing the problem.

Quickly explained, you should do 2 runs to see the problem. The first run creates a matrix and a table, and stores the values in a DataTable cell. You shouldn't see any problems there.

Save the document and close it.

Then open the file once again, but just run the 2 commands in chapter 4. You should then see an error message.

My goal is to be able to save a nested variables with its values in a Datatable between sessions. The main variable and many of them below are tables, the last in the branch often string values or numbers with units.

StoreBetweenSessions.mw

I want to make proc that returns expression sequence of two numbers, say. A,B

This will be the normal return, but if the proc encounters an error, it should return FAIL. But this is not possible, because if I type A,B:=foo(0) and foo() happenes to return FAIL then Maple will complain

Error, mismatched multiple assignment of 2 variables on the left side and 1 value on the right side

The three workarounds I see are these

Method 1

I could wrap foo() with try/catch and have foo throw an exception when it encouters an error instead of returning FAIL, but I do not like this. This will look like

restart;
interface(warnlevel=4);
kernelopts('assertlevel'=2):
foo:=proc(n::integer)::integer,integer;
  if n=0 then
     error ("encountered error");
  else
     return 1,2;
  fi;
end proc;

And now the caller will do

try
   A,B:=foo(0);
catch:
   print("encountered error");
end try;

method 2

Another option is to have foo() return ONE value back. In the case of an error it will be FAIL, and in the case of normal behavior, it will be a LIST of the two items, which then I have to extract.  Like this

interface(warnlevel=4);
kernelopts('assertlevel'=2):
foo:=proc(n::integer)::Or(list(integer),identical(FAIL));
      if n=0 then
         return FAIL;
      else
         return [1,2];
      fi;
end proc;

And now the caller will do this

L:=foo(1);
if L<>FAIL then
   A:=L[1];
   B:=L[2];
else
   print("failed call");
fi;

But this is not as easy as just calling foo() as   A,B:=foo() but I can't do this due to the mismatch problem.

Another method, commonly used in C programming is to have the function return status an additional output and this will indicate if the call was success or not. so the caller has to remember to always check for this before using the returned values. These are handled by errno, perror(), strerror(). But for now, lets make the function return the status.

So caller will first check if status is success first and if so, then it will read the actual returned values that follow it. Like this (status is true/false)

method 3

interface(warnlevel=4);
kernelopts('assertlevel'=2):
foo:=proc(n::integer)::truefalse,integer,integer;
  if n=0 then
     return false,0,0;
  else
     return true,1,2;
  fi;
end proc;

And the caller will do

status,A,B:=foo(1);
if status then
   print("call was success, A and B are ",A,B);
else
   print("call failed");
fi;

So the return values will always have status as first argument that the caller has to check before reading the rest of returned values.

From the above three options which you think is best?

Anyone can suggest alternatives to the above methods?