I think I remeber doing this before but not sure and it is not in my cheat sheet.

Given an expression, I wanted to find all names in it. Which can be done using indets(f,name);

But then how to check if any of the names found are not in the Maple initial known names given in https://www.maplesoft.com/support/help/Maple/view.aspx?path=initialconstants

For example,

f:=x^2 - y^2+Pi;
indets(f,name);

Gives {Pi, x, y}  how does one then check if this list does not have any known name in it?

In this case Pi. I do not want to check explicitly for each name listed on the web page above.

Are these initial known names  grouped in some specific maple type that can be used to check against?

Or is there a command in Maple to return a list of all these initially known names? If so this list can be used to check against.

Asked google AI and it did not know.

Maple 2025.2

Is the following behavior expected? using  t=0 .. 3*Pi  vs.  t=0 .. round(3*Pi) give different plots.  Why? Should not the plot be the same?

ps. do not know if I asked this before or not. I can't remember. Search in Mapleprimes is not easy.

Download deplot_with_round_jan_17_2026.mw

WHen plotting f(x) and g(x) on same plot, and putting legend at bottom (default), the legends show horizontally. i.e. f(x) then g(x) on same line.

I'd like the legend to be stacked vertically, just like when the legend on the right or left, But keep it at bottom. But want to do all this in code. Not using any UI context tools or mouse.

Here is an example

Download legend_question.mw

Given equation such as 1/A=x/A, at school we are allowed to write this as 1=x by canceling A on both side.

But in Maple, even if I tell it that A is not zero, it still refuses to simplify it and cancel A from both sides.

What could be the reson for this?

eq:= 1/A = x/A;
simplify(eq) assuming A<>0

Using Mathematica it does it:

I am not looking for workaround, I know how to force this if needed, one way could be

numer(normal((lhs-rhs)(eq)))=0

gives 1 - x = 0

My question is why Maple's simplify does not simplify it automatically? Even using simplify with size option did not. Is it just weakness in simplify or is there a subtle mathematical reason behind it which I am missing?

Maple 2025.2

Given first order nonlinear ode which is hard to solve using standard methods, the smart dsolve sometimes uses a method where it linearizes the first order ode to a linear second order ode and solves that.

Then with that solution to the linear second order ode, it is able to find the solution of the first order ode (need to resolve the constants of integration to merge them into one, but this part is easy to do).

My question is, how and what method it uses to "linearizes by differentation"? I could not find this in any textbook I have, and not able to see how it does.

Here is an example where it uses this method to solving this first order ode

restart;

Typesetting:-Unsuppress('all'); #always do this.
Typesetting:-Settings(prime=x,'typesetprime'=true); #this says to use y'(x) instead of dy/dx    
Typesetting:-Suppress(y(x)); # this says to use y' and not y'(x)

ode:=diff(y(x),x) = (-y(x)^2+4*a*x)^2/y(x); 
infolevel[dsolve]:=5;
dsolve(ode,y(x), singsol=all);

Tracing says 

So it says, if I understand, that it differentiated the original given first order ode and then linearized the resulting second order ode to the above, which is    y''=-64 a^2 x^2 y - 16 a x y' which is certainly linear second order ode and now can be solved using kovacic algorithm. Now the solution to the first order ode can be obtained.

But when differentiating the first order ode, this is the result

expand(diff(ode,x))

So the question is, did Maple mean it "linearized" the above to y''=-64 a^2 x^2 y - 16 a x y' ? 

If so, then how? Did it use Taylor series? but if so, where it expanded about? Or did it use some other method?  One thing I noticed is that by multiplying the RHS above by y^2 it becomes

And "removing" the nonlinear terms (say expansion is around y=0, so higher order y terms are very small and can be removed) the RHS above becomes

    y'' y^2 = -16 y' a^2 x^2 + 32 a^2 x y

Which is close to Maple shows, but 32 instead of 64, and what about the y^2 on the left side?  Is this method even valid mathematically to do? Since solution that result will be correct only near y=0?

So far, trying to step in the debugger to find how, I was not able to find where it does that but will keep trying.

Any idea what Maple means by linearization to 2nd order and how it does it?

ps. only case I know about, where nonlinear first order ode can be transformed to linear second order ode is the Riccati ode using transformation y=u'/u. But this  first order ode is not Riccati.