@lemelinm Your question caused me to update the instructions for the video, which I quickly shot for my students. However, I think I should reshoot it to describe the multiple ways of working with the maple.ini file. Unfortunately, most of my students use a Mac and so I don't know any of the complexities of working with that system. 

@C_R Thanks. I'll add your comment to the bug report I submitted on the beta website when it returns. (I would say the website is taking a Thanksgiving break, but the Canadians already have celebrated Thanksgiving. So, I'm not sure what is going on.) 

@lemelinm For some projects, I will have a special maple.ini file. I put the maple.ini file in the directory where the worksheets are stored. Then, when I "double-click" on the worksheet, which forces the working directory to be the one with the worksheet, that maple.ini file is loaded. 

Putting a maple.ini file in the users folder is the universal file used if there is no maple.ini file in the working directory. 

@lemelinm 

Alternatively, if you use different maple.ini files for different versions like I do:

1) Create a folder in the "c:/Program Files/Maple 2024" folder called "users." Usually, the folder is not there. 

2) Copy the maple.ini file into the "c:/Program Files/Maple 2024/users" folder. 

Sometimes, when I start mistyping the word dsovle, delete a couple of characters, and the font changes from then on to a non-italicized font. I can get it to go wrong when I hit the "evaluation" icon in the palette. That is the one that says f(x), vertical bar, y = x. 

As far as I can remember, I have never observed this behavior in previous versions. I still prefer to edit in v2023. 

@lemelinm I have access only to a physical US keyboard, so I have always wondered about the shortcut key options. I appreciate you telling me such a choice is not available. None of my international students mentioned this fact. I sense a short video showing folks how to access the Accents Palette (hidden by default) and then save the icon to the Favorites would be useful. 

Yep, after a while, if too many favorites are saved, it no longer becomes a time saver. I do appreciate the folks at Maplesoft added the feature of being able to arrange icons. 

@acer It is all good. The more I read, the better I am informed and the better I can help others. As I said, I have always used the add procedure for these types of situations. But there is no doubt the sum procedure is getting smarter and more innovative. Hence the motivation to learn more. 

@lemelinm I'm probably the number one whiner on the beta test site about how export/print fails to generate a reasonable PDF. But I need to use it all the time, such as on my webpage. In my opinion, the PDF print or export routine has gone backward ever since the implementation of the print layout mode. I like the idea of print layout mode.  But for some reason, the spacing of lines or graphs never works. What you see is not what you get. (2023 was not bad. I simply don't print in 2024 .) 

The folks at Maplesoft are very nice and encourage me to report bugs. However, it wouldn't surprise me if they decide to block my account once the beta of the 2025 version comes out. (For our Canadian friends, that last sentence was an example of sarcasm. 😁 ) 

@acer It was very nice of you to take the time to write out a detailed explanation. However, I would have been offended if you had simply said, "Click on the magenta error message link and READ IT!" The page not only contains an explanation, but it includes the method @nm pointed out. 

Too frequently, the magenta error line leads to no page. Consequently, I never click on it. Lesson learned. Don't assume there is nothing at the end of the magenta link. 

Yes, the help page for the sum summarized what I have told others - use add when adding discrete quantities.  

However, I realize now that I wrote the question poorly. I was more interested in discovering more about what happens internally in Maple. Printlevel wasn't sufficient. Let me do more reading the chapter on Debugging before I return and ask another question that causes me to end up with egg on my face. LOL!

@lemelinm My apologies, Mario. I did find a post you made to one of my videos, the Statistical Mechanics video. Normally, questions that I have not responded to are held for me to work on. This one slipped by. 

 All of my documents, either in PDF or Maple-worksheet format, are found on my web domain, gould.prof. So for the physics ones I'm working on, go to gould.prof/learning-physics . 

@Aung, What is the difference between your original problem and this one? I don't see it. If you identify the only difference, then you might be able to use the same procedure I used.

@acer A fun and informative solution. I saved it so that I can pass it on to others. 

@sidyly1211 Are you satisfied with @acer's solution? 

@Paras31 I don't know why the arrows don't show up. Your system is nearly identical to example 3 in DEtools, DEplot and that one lacks arrows. 

Change your system to y'(t) = u(t), u'(t) = -y(t) and the arrows will appear. Same graph. (And for fun, animate the curve.)

MaplePrimes_DEplot.mw

@acer I enjoyed and valued everything you wrote because it forced me to think again about why I tend to recommend "output = listprocedure" over the default. I recognize the value of odeplot and why it was created. I recognize the speed advantage. However, I value simplicity and maximizing productivity with the fewest amount of commands. Remember to add "pitick" (which I misread as "pit-ick") when it is not necessary violates my philosophy. 

The great thing about Maple is that both new and infrequent users can use it while providing a way for faster calculations for more intensive users.  I evaluate other systems but keep returning to Maple because while others can be simpler to use, there is often a calculation/programming ceiling with them. On the other hand, those without ceilings, such as Mathematica or Python, require more engagement to use at the most basic level. (They have become easier because of github and LLMs.)