Perhaps:

Round:=(x,digs::nonnegint)-> evalf(round(x*10^digs)/10^digs);

@Kitonum or last line could be add(Dists)/20;

@lcz I haven't used Maplets, but an option like foreground=red can change some things, e.g. in a TextField or Button, though I don't see how to do it for GridLayout.

@Carl Love This leaves "1" as nonlinear, which is not what the OP wanted.

@Carl Love OP's code looks at nops, so would have 3*x nonlinear. But perhaps the ground rule excluded that: "can be any combination of the given variables, that is, x, y, and z", which made me wonder if "y*y" would count.

@Stretto The rectangle and cursor mechanism in a code edit region works in the same way as for 1-D. I'm not aware of cases that don't work.

@Anthrazit Do(%MathContainer0 = evalf[3](a)); will give you 3 sig fig (not decimal digits, which is harder to arrange)

You can of course use a math container as a label by making it not editable.

@Christopher2222 Yes, the help says only grayscale tiff output is possible if it isn't coloured.

@Carl Love Thanks for catching that. I do know the rule, but was careless when I looked at the mass of Maple output - thinking I had a list of lists. I still find it confusing - when I look at the complicated mess that is evals before setting phi=Pi, which as you say is a Vector, it displays as a list of lists, with each of the entries having square brackets around it.

@Jjjones98 There is no two-sided (forward) laplace transform in inttrans. Not sure what the two-sided inverse laplace would be, since the contour already runs g-I*infinity to g+I*infinity.

If I change the last line to have i = 0 .. 200, 100 then I get a list of 3 numbers as expected (after about 45 seconds). I'm guessing it could be made more efficient by implementing the trapezoidal rule (or similar) for your integrals.

Of course I didn't guess. Nice implementation of a spigot algorithm.

@Jjjones98 invfourier(expr, w , t) doesn't make sense if expr contains t; you would be going from the time domain to the time domain.

@Jjjones98 So invfourier cannot evaluate it, without more information, perhaps specifying values of some constants. Working with any expression that has general roots of a quartic polynomial will be almost impossible. But something is very strange since you inverse laplaced into the time demain and then inverse Fourier from an expression with t in it, into another time domain. ??