is it possible for a string such as "res:=boo()" to be evaluated after calling parse, and have res have the value that the function boo() returned?

Now, it does not work. I must do   res:=eval(parse("boo()")) , meaning the result of the call to boo() is outside the string.

Here is an example of what I mean

boo:=proc()
   return 99;
end proc;  

foo:=proc()
  local s,res,i;
  s:="res:=boo()";
  eval(parse(s)):
  print(res);
end proc;

foo();

The above does not work. It displays res but this works

boo:=proc()
   return 99;
end proc;  

foo:=proc()
  local s,res,i;
  s:="boo()";
  res:=eval(parse(s)):
  print(res);
end proc;

foo();

The above works, and prints 99.

The reason I am asking, is that I was thinking of storing in a data base the complete Maple command as string, along with the LHS of the call, and just load the string the evaluate it, and it will have res automatically set.

It is no problem if this can't work, I could always just eval the command itself, without the assignment being there. Just thought to ask if there is a way.

I have about 30 modules under one root common module.  The total code is about 25,000 lines.

Currently during development, when I change a line of code and want to run a test, I just do

interface(warnlevel=4);
kernelopts('assertlevel'=2):
read   "my_root_module.mpl";
#run some test 

From a worksheet. This works fine, but it is very slow. it takes now about 8-10 minutes to finish each time.

So each time I make small change to the source code, which all sit in separate .mpl plain text files, I have to wait and wait for the read to complete.

This is way too slow. 

The thing is, my my_root_module.mpl files includes child modules (using the $include directive), and each child module might also have $include to pull in its own child modules, if any. Each module is onbe separate .mpl file.

So at the end my_root_module.mpl will end up reading all the code, which is now about 25,000 lines over 30 or so modules. Here is an example of the layout I have

my_root_module.mpl
=======
export my_root_module:=module()
$include  "B.mpl"   
$include  "C.mpl"                            
$include  "D.mpl"   
   export foo:-proc()....     B:-foo().... end proc;
end module:

B.mpl
=======
local B:=module()
$include  "B1.mpl"   
$include  "B2.mpl"                            

   export foo:=proc()..... end proc;
end module:

C.mpl
=======
local C:=module()
$include  "C1.mpl"   

   export foo:=proc()..... end proc;
end module:

etc...

There must be faster way to do this. Having to wait about 10 minutes each time to test one small code change each time is not practical.

What do others do when they develope large code in Maple? Is this a typical time?

I do not want to break my main modules into separate name spaces again in order to  use separate mla for each module, so that my changes only affects one mla file.  This will speed things, as I would then only have to rebuild one small modules, the one I changed.

But I want to put all my modules under one common module, which acts just as a common name space, and have only one mla file.

Are there ways to speed  reading mpl file?

Edit

Thanks to all the answers. It turned out indeed to be the slow Maple GUI again. The option interface(prettyprint= 0) did not help in the worksheet to speed the GUI.

I wrote the commands to read the mpl file and build the mla in a file, and used the DOS command line, and turned off the warning messages using DOS option, and now it finished almost instantly.

"C:\Program Files\Maple 2021\bin.X86_64_WINDOWS\cmaple.exe" UPDATE_MLA.mpl 1> nul

    memory used=18.6MB, alloc=73.3MB, time=0.52

Notice, in the above 1>nul will not even display the warning messages on the terminal. 2>nul does not work, since these are not error messages. Here are the different redirection options from the net

But even without using this redirection, and keeping the messages scroll on the terminal, it was still very very fast from the command line

I complained about how slow the Maple Java GUI when it comes to scrolling and how it can can cause  slow down many times before, so will not complain again about. May be one day Maplesoft will fix this.

Hi MaplePrimes team,

I want to create two 3d surfaces with plot3d command in Maple, one of which represents a light-emitting diode (LED).

For that, my idea is simple: Just to disable the shade on a specific surface (representing the LED-like) among other surface. So, whatever the direction of the light, the LED surface keeps a constant luminosity.

Unfortunately, the glossiness = 0 option is still dependent of light direction.

I looked at all the options for plot3d and display commands, but I couldn't find anything for disable light on special surface.

Maybe in PLOT3D command?

If not, is there an option to add a second light source?

Simple example I would like create:

- 1. A surface with regular light:

BALL := plot3d(<cos(t)*cos(s), cos(t)*sin(s), sin(t)>, s = 0..2*Pi, t =-Pi/2..Pi/2, color = "Blue"):

- 2. An illuminated surface representing the LED:

LED := plot3d((<2 + cos(t)*cos(s), cos(t)*sin(s), sin(t)>, s = 0..2*Pi, t =-Pi/2..Pi/2, color = "Yellow", What option to insert?):

Then, the assembly will give:

display(BALL, LED);

My Advanced Applications Tests in Maple

Figure 1: Aisle LED light and LED-screens of first-class seats in an illuminated cabin on board of an aircraft.

Figure 2: Here is the problem in the darkness. The aisle LED light and LED-screen must be stay constantly illuminated for any direction of light.

To better understand my objectives, here is another image using lights. Note that the LEDs (pale yellow strip shapes) stay constantly illuminated whatever the daylight and therefore allowing the aircraft to be visible.

Figure 3: Exterior lighting systems and dazzling jet engine afterburner of a military transport aircraft concept.

Thank you for your time.

Best.

Guy.

Please help to find the exact solution of any ODE by the >sinh or cosh method. I have attached arbitrary ODE here:

>ode:=U""+c^2*U"+k*c*U"-(3U^2+a)*U''=0

I need to get more tickmarks in my plots by reducing the size of fractions produced by Maple.
For example, instead of (3*Pi)/10, Maple gives me (3/10)*Pi. Any help would be appreciated.
I can actually convert all there Maple numbers to fractions, but Maple will not accept these conversions as tickmarks.
Thank you.
mapleatha

fd := fopen("temp_file.txt", WRITE);
Error, (in fopen) permission denied

It is giving this error even to my download folder as I am able download files via internet can someone help with a small program to creating file and writing to it in maple.

Kind help it will be acknowleged

1) Without the aid of a graph, find the absolute maximum and minimum values of the function

f(x)=36x⁶ +2665x⁴ +240x−675+4534x² −5836x³−516x⁵ over the interval [0,4]

2) Find points P and Q on the parabola y = 1 − x ² so that the triangle ABC formed by the x-axis and the tangent lines at P and Q is an equilateral triangle.

I need tto change the color of a word or a math expression inside the title of a Maple plot.
For example, I need to have sin(x) in red in this axes plot:

AX:=plot([[x,0,x=0..Pi],[0,y,y=0..1]],color=black,thickness=3,title=typeset("\nLeft Riemann Sum for the Function:\n",sin(x), "on the interval ", [0,Pi]\n),titlefont=["Arial",25]):

How do I do it?

Thank you!

mapleatha

Hi,

I want to solve a set of ODE(s) by Maple. How do I do that?(Please, see the attached file)
Thanks.

new.mw

Kind help Given graph G and an edge say (u,v) 

how to get the number of vertices of G which are shorter distance v than from the vertex u

Similiarly the number of vertices of G which are shorter distance u than from the vertex v

Kind help if anyone possible. I apologize to distrurb I would 200% acknowedge and merit your efforts.  

Suppose I have a matrix say

A:=[[1,2,3],[3,4,5],[5,6,7]]

If I want to get the sum of all the elements of the matrix.

Kind help if any one.

I apologize for the disturbance

Send my matrix to word as matrix either via maple or phython

Say we have 

A:=Matrix([[0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0], [1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0], [0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1], [0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0]])

How to write this matrix to a word file in a matrix form

In general If I have a n cross n matrix  How to write this matrix to a word file in a matrix form

This a Adjacency matrix

If I have several n cross n matricies I want them to be fprintf in the same file one after other giving paragraph space with some name of the matrix at the top.

I'm practicing with matrices in Maple, but I have a question. My question is, how do I set up the differential equation system on matrix form x '(t) = Ax (t) + B?

Here are the equations:

x'₁(t) = x₁(t) - x₂(t) - 3

x'2(t) = 12x₁(t) - 8x₂(t) + 4

I've been looking around for some help sources, but the only one I could find is this. I tried to set it up like that, but didn't work, it gave me an error.

How should I set it up (using Maple commands)?

I have found an unpleaseant feature of the define command. 
@Carl Love
See below for the example. Basically, after declaring a function orderless via the define command, 
a simple use of Categorize stops working.  Details in the file. 

How can one define a function f(x,y) to be symmetric under interchange x<-> y

 primes2.mw

In this worksheet, how do the several successful plot commands evaluate the complex expression being plotted, and why do the unsuccessful plot commands fail to do so?

Plot_complex_expression.mw