@bnpndxtrwp The "original example" that you refer to may be older than Maple's Vector and Matrix (capitalized) commands. It may have been true that a vector (lowercase) of lists was more efficient than other container structures available at that time.

That being said, I'm not claiming that a Matrix is the most efficient structure to use. To ascertain that, I'd need to see the full range of ways that you use it. Rather, I recommend a Matrix because of the great flexibility of its indexing.

Partial answer: Somewhere in your input expression(s), you've used square brackets for algebraic grouping. This is not allowed; you must used round parentheses. However, this answer doesn't explain the undefined. You'll need to upload your worksheet, or at least your input.

Your anger is blocking your ability to learn.

@nrussoniello In 2003 I wrote a Maple program to compute the rank of a matrix of rational functions over the rationals (in any number of variables) by random numeric assignments to the variables (akin to VV's method). By working over finite fields, I was able to compute a provable upper bound on the probability that that computation did not give the correct rank. Those upper bounds were infinitesimal, typically about 10^(-30), and could be made arbitrarily close to 0 by making the random selections from a larger finite field or by using multiple random selections. The time needed to compute exactly the rank of a matrix over a finite field with characteristic < 2^25 is trivial.

I won a 1000-euro prize for that program/proof.

@nm It's a mystery to me and a great Question: Is using restart equivalent to starting a new kernel? Your experience here suggests that they aren't equivalent. Hopefully someone else can provide more insight.

@David Sycamore To make the requested change, you simply need to replace

`+`(convert(j, base, 10)[])

with

j

The key is to use convert(..., polynom) (as discussed in the replies to one of your other Questions) to convert the unwieldy series structures (produced by taylor) into Maple's standard algebraic forms. And do you want a O(...) term in your final output?

It would be much easier for me to show you how to do it if you upload a complete worksheet using the green uparrow on the toolbar of the MaplePrimes editor.

I edited the title of your Question to remove the phrase "in 2-D output" because I think that using that phrase confuses the issue. As I said elsewhere, the form of the output has no bearing on how it's treated by subsequent input.

I changed the title of your Question so that it doesn't look like spam. If my new title misrepresents your intent, feel free to edit it again.

By the way, as far as the input commands are concerned, output is just output; the fact that it's 2D output makes no difference. Indeed, any output can be displayed in 1D form by

lprint(%);

@nhmacuk Sorry, I misunderstood the Question. You mean to expand it algebraically. By "expand 2D output", I thought that you meant that you wanted it to appear wider on the screen by using explicit *s for multiplication signs.

@nm Do you put the restart in its own execution group? Sometimes that makes a difference (although I think that that's unlikely in this case). Nonetheless, you should get in the habit of always putting restart in its own execution group, if you're not already.

@nm Whether to ignore or to error is up to the programmer. They can make it error by making $ the last parameter. Most modern library code uses this if it's appropriate; most older library code does not. 

Note that ignoring them can be useful if they're going to be passed on (via _rest) to some other command. I usually do this with procedures that call plotting commands.

@nm Sorry, I misread "does" as "doesn't". My fault.

So what about the memory usage?

The mserver to kill is the one that has a consistent non-zero value in the CPU% column.

@nm I guess that by "it worked" you simply mean that there was no error. It's simply ignoring it, just as if you'd used foo= [boo] as the last argument.

Yes, mserver.exe is the same thing as the kernel.

You say that when you press "interupt the current operation", it doesn't work. (Yes, I've experienced that many times.) So, how are you able the enter a restart command?

While it is hanging, if you go to Windows Task Manager, what is the percentage reported on the column header for memory? In other words, what percent of your total memory is in use?

If the hanging computation is within the kernel (as opposed to being due to the GUI's inability to display complex or lengthy output), then you do not need to close the entire Maple session in order to start a new kernel. All that you need to do is kill the kernel from Windows Task Manager, save the worksheet, and reopen the worksheet (dismissing the dialogs about the dead kernel). I find this to be much faster, and also you lose nothing from your worksheet(s).