## Maple 2020 Sheet now opening in 2021, 2022, and 20...

I have a calculation sheet that used to work in Maple 2020 and earlier, but with an upgrade to versions 2021 to 2023 the same errors are appearing. The sheet still functions fine in 2020 but unknown why these errors appear when using 2021 thru 2023.

Does anyone know what might have changed with the later versions to result in these types of errors?

## How do I vary the action that I write in attachmen...

Hi . My question is about writing a gravity equation, which I explained comprehensively I  explain in the PDF linked below, and I need the code for this equation in Maple.

My_Question2.pdf

## How to write the equation of the planes tangent to...

list:= [[-12, 3, 5], [-11, -2, 5], [-11, -1, 2], [-11, -1, 8], [-11, 0,
1], [-11, 0, 9], [-11, 3, 0], [-11, 3, 10], [-11, 6, 1], [-11, 6,
9], [-11, 7, 2], [-11, 7, 8], [-11, 8, 5], [-4, -9, 5], [-4,
3, -7], [-4, 3, 17], [-4, 15, 5], [-3, -9, 2], [-3, -9, 8], [-3,
0, -7], [-3, 0, 17], [-3, 6, -7], [-3, 6, 17], [-3, 15, 2], [-3, 15,
8], [-2, -9, 1], [-2, -9, 9], [-2, -1, -7], [-2, -1, 17], [-2,
7, -7], [-2, 7, 17], [-2, 15, 1], [-2, 15, 9], [1, -10, 5], [1, -9,
0], [1, -9, 10], [1, -2, -7], [1, -2, 17], [1, 3, -8], [1, 3,
18], [1, 8, -7], [1, 8, 17], [1, 15, 0], [1, 15, 10], [1, 16,
5], [4, -9, 1], [4, -9, 9], [4, -1, -7], [4, -1, 17], [4,
7, -7], [4, 7, 17], [4, 15, 1], [4, 15, 9], [5, -9, 2], [5, -9,
8], [5, 0, -7], [5, 0, 17], [5, 6, -7], [5, 6, 17], [5, 15, 2], [5,
15, 8], [6, -9, 5], [6, 3, -7], [6, 3, 17], [6, 15, 5], [13, -2,
5], [13, -1, 2], [13, -1, 8], [13, 0, 1], [13, 0, 9], [13, 3,
0], [13, 3, 10], [13, 6, 1], [13, 6, 9], [13, 7, 2], [13, 7,
8], [13, 8, 5], [14, 3, 5]];
These points are lies on the sphere (x - 1)^2 + (y - 3)^2 + (z - 5)^2 = 13^2. How to write the equation of the planes tangent to the sphere at the points in the list? This is some equations.
I tried

restart;
with(geom3d);
L := [[-12, 3, 5], [-11, -2, 5], [-11, -1, 2], [-11, -1, 8], [-11, 0, 1], [-11, 0, 9], [-11, 3, 0], [-11, 3, 10], [-11, 6, 1], [-11, 6, 9], [-11, 7, 2], [-11, 7, 8], [-11, 8, 5], [-4, -9, 5], [-4, 3, -7], [-4, 3, 17], [-4, 15, 5], [-3, -9, 2], [-3, -9, 8], [-3, 0, -7], [-3, 0, 17], [-3, 6, -7], [-3, 6, 17], [-3, 15, 2], [-3, 15, 8], [-2, -9, 1], [-2, -9, 9], [-2, -1, -7], [-2, -1, 17], [-2, 7, -7], [-2, 7, 17], [-2, 15, 1], [-2, 15, 9], [1, -10, 5], [1, -9, 0], [1, -9, 10], [1, -2, -7], [1, -2, 17], [1, 3, -8], [1, 3, 18], [1, 8, -7], [1, 8, 17], [1, 15, 0], [1, 15, 10], [1, 16, 5], [4, -9, 1], [4, -9, 9], [4, -1, -7], [4, -1, 17], [4, 7, -7], [4, 7, 17], [4, 15, 1], [4, 15, 9], [5, -9, 2], [5, -9, 8], [5, 0, -7], [5, 0, 17], [5, 6, -7], [5, 6, 17], [5, 15, 2], [5, 15, 8], [6, -9, 5], [6, 3, -7], [6, 3, 17], [6, 15, 5], [13, -2, 5], [13, -1, 2], [13, -1, 8], [13, 0, 1], [13, 0, 9], [13, 3, 0], [13, 3, 10], [13, 6, 1], [13, 6, 9], [13, 7, 2], [13, 7, 8], [13, 8, 5], [14, 3, 5]];
eqS := Equation(sphere(S, (x - 1)^2 + (y - 3)^2 + (z - 5)^2 - 169 = 0, [x, y, z], 'centername' = T));
k := [seq](sort(Equation(TangentPlane(P, S, point(A, pt[])), [x, y, z])), pt in L);
seq([L[i], k[i]], i = 1 .. nops(L));

I get

With each equation has the form a*x  + b*y + c*x + d=0, how can I get in the form igcd(a,b,c,d) = 1 and a >0. If a = 0, then b>0; If b = 0, then c>0.

PS. I use this expr := sort(primpart(3*x + 6*y + 12));
expr*signum(lcoeff(expr)) = 0;

But I do not know use it in the seq k

## System of two equations and evaluate...

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 > WhyNot3 := proc (alpha, delta) if not [alpha, delta]::(list(numeric)) then return ('procname')(args) end if; FirmModelHmax(alpha, .2, delta)[3] end proc: pltHmax1 := plot(   [seq(WhyNot3(alpha, delta),delta=0.1..0.5,0.2)]     , alpha=0..2/(2 + 0.2*(1 - sqrt((c - s)/(v - s))))        , linestyle=[dot,dashdot,dash]       , legend=[seq('delta'=delta,delta=0.1..0.5,0.2)]       , legendstyle=[location=left]       , labels=["alpha","Firm profit"]       , labeldirections =["horizontal", "vertical"]     , legendstyle=[location=bottom] ): display(pltHmax1)
 >

## Unable To Type In Maple, No Cursor...

I am currently unable to type in maple 2021, there is no cursor, nothing shows up when I type etc. I am also unable to save files. I went into document mode, nothing. Some of the dialogs don't show up. Where does maple save documents and how do I change that setting? That might be my problem. Furthermore, there are no tabs visable, like I can't access any documents I open.

## How can I select four points on a sphere to make a...

I have the sphere x^2 + y^2 + z^2 =( 33*sqrt(3))^2 and I want to select four points on a sphere to make a regular tetrahedron so that its coordinates are integer numbers. I see this question is here https://mathematica.stackexchange.com/questions/289123/how-can-i-select-four-points-on-a-sphere-to-make-a-regular-tetrahedron-so-that-i
Time to get result is a problem.

## Error, too many levels of recursion...

Due to a stupid typing mistake I get this error, "Error, too many levels of recursion". Now the program is frozen and I cannot get rid of the error.  Help!

## Laplace Equation...

How can a solve second order Laplace Equation with boundary condition numerical in Maple 2023?

Kjell

## Configuring dark mode via Xresources...

Hi,

Im trying to configure Maple's colors by modifying the X11_defaults/Maple file but nothing happens. I set the environment variable MAPLE to point to my Maple installation and load the previous file with xrdb. I am running dwm as my window manager in Arch Linux.

I am frustrated. All help is welcomed. If you have any suggestion for configuring dark mode in a different way, please share your arcane knowledge with me.

## How to extract numerical values from an expression...

I have an expression of the form X=a/f^b where a and b are both numeric. How do I elegantly extract the numerical values of "a" and "b" given X? See below for my kludge solution.

Problem: extract two numerical values from an expression. Surely there is a more elegant way?
Here is the form of the expression.

 > restart; X:=a/f^b;
 (1)

Find a and b when they are numbers.
X1:=subs(a=1.234,b=6.789,X);

 (2)
 > indets(X1); fterm:=op(2,%); log(fterm);This sometimes works and yields 6.789*log(f) but I've never been able to figure out when it is going to work and when it won't work. #log(fterm,f);This never works
 (3)
 > b:=-op(2,fterm);
 (4)
 > a:=X1*f^b;
 (5)

Isn't there a better way? This requires that the "op" indices won't ever change and that is asking a lot if this is embedded in a larger program.

## Cannot map a function with `mod`...

I am slightly confused as I can't apply the seemingly correct function to a sequence. It seems like `modp` does not like my inverse. But I am not aware of any other way of finding the modular inverse.