C_R

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These are replies submitted by C_R

@Axel Vogt 

Maybe this example explains better where I am stuck

`^`(`^`(a + b, 4), 1/2);
                                  (1/2)
                        /       4\     
                        \(a + b) /     

This cannot be written with compound procedures (or operators in this case, which are procedures themselves if I am not mistaken). Here is an attempt

(`^`@`^`)((a + b, 4), 1/2);

which can be modifed this way not make it work

(sqrt@`^`)(a + b, 4);

But what can be done if powers other than 1/2 are involved? There seems to be no way to pass extra arguments.

I am inventing now code to show a structure that separates (names of) procedures from arguments (using the % symbol do indicate that the output from the preceeding procedure call is used)

(`^`@`^`)([(a + b, 4)],[(%, 1/2)]);

These examples are trivial. However, sometimes compound procudure calls are quite handy for example to simplify expression, where a sequence of commands expand, factor, normal, simplify, ... are effecitve. However, when extra arguments (for collect for example) are required procedure composition does not work any more.

Maybe there  are other ways than functional programming using the ()() construct to do this. One could think of a procedure with a long list of arguments starting with a sequence of procedure names followed by a stack of parameters that is processed from the left to the right. However, this would probably not be easy to read, although compact.

@yasi add the view option to Roubens answer (here with 0.01 instaed of 0.0001)

plots:-display(plot(x^2, x = -1 .. 1, linestyle = dot), plot(x^2 + 1, x = -1 .. 1, linestyle = spacedash), plot(x^2 + 2, x = -1 .. 1, linestyle = dashdot), thickness = 3, view = 0.1e-5 .. 0.01)

 

Yes on two computers and with two browsers.

I had a suspicion that a VPN connection was responsible for that but his was wrong.

@acer 

Thank you all. This was copied code I modifed to test a triangular domain. I overlooked the restart...

Nice modification of the range by the way.

Just a comment: What makes your example challenging is that "Expression of secondary variables" still contains the primary variables.

I think there is a way if you could provide the equation and tell what the terms with the double bar stands for (i.e. provide the equations). This would make answers easier.

PS.: I also get two images

It's the other way around: You can use ChatGPT from Maple. Have you read this post?

@Rouben Rostamian  

Tricky to get a perfect match. See here for details. I hope I have descirbed your simulation correctly.

I have noticed a dependency on zoom settings (with crtl and mouse-wheel)

 

@Preben Alsholm 

Thank you for confirming. Initially I tought that the effect was caused by the Windows 10 switiching from high resolution  mode to 1920*1080. However I cannot reproduced this at the moment (changing the resolution by hand). Maybe restarting the explorer (which I did for other reasons(network...)) set the system into a state where appropriate fonts are used (that match the display resolution).

I also checked if the effect is related to the use of internal and external graphic adapters (with negative outcome at the moment).

My hypothesis is that (in some system states and/or system configurations) slim high resolution fonts are incorrectly down sampled by software. This erases fine lines.

@acer 

Sorry, I was too short. I only wanted to say that _Z in a RootOf expression (my first example) is only a placeholder that has not been assigned to anything whereas _Zxx from my second example comes with assumptions. Both are outputs of solve but completely different things. I unconsciously mixed them up switching between the two examples.  

_Z is of course a complex unkown. Now that you've said it. It makes sense not to change to something else. The RootOf help page would profit form this mention even if it is obvious for readers with a solid mathematical back ground.

@acer 

Studying your last reply, I just realised the double use of _Z... That clears up some open points! Can _Z be changed to _X?

restart;
solve(sin(x)/x, allsolutions);
about(_Z1);
solve(x^x = 1/sqrt(2), allsolutions);
about(_Z);
                        Pi (2 _Z1 + _B1)

Originally _Z1, renamed _Z1~:
  is assumed to be: integer


                          /     _Z    (1/2)\
                    RootOf\-2 _Z   + 2     /

_Z:
  nothing known about this object

 

@acer 

I want to query subexpressions of a special type but did not get there with the originally posted example. I understand now that this can be fixed by using indets@@2 only because _Z is the argument of ln. 

What I want finally to achieve: I would like to extract names of the kind _name~ or _name from solve output and replace it by something better readable (i for example) and then stating right to the ouput that i is element of N or Z. For example for

restart;
solve({tan(x)/x,x>0},allsolutions)[];
a:=indets(%);
whattype(a[1]);
whattype(_Z1~);# I cannot see an index in the output of solve

The goal would be to generate textbook style output like

I tought about using a type identifier on the output of indets that selects all _name~ or _name expressions and then generating subsitutions. Doing this by hand only works once. When new dummies are created the manual substitutions fail.

I have tried to identify the type of the dummies to use the returned type to filter out only dummies but if it is true that the dummies are of type symbol then this type is too unspecific. This is a bit off topic: Are there other identifiers that could work?

I still do not fully understand the meaning of index in "dummy index name".

Update:

I have found an identifier that works: indets(..., suffixed(_, symbol))

I think I also understand now the meaning of index. If I am not mistaken it is the number after _Z in _Zindex. It is not an indexed name (?indexed). The output of whattype(_Z12~) is still unclear. This is not explained ?type,indexed. Anyway

Thank you for your time!

@emendes 

I got the same remark about the download size from one of my colleagues who only needed to view a document but not to play it.

Viewing Maple documents on a wide screen is often better than viewing pdf with page breaks.

Have you tried to set the page to A3 or A2 and to landscape to make the table fit on one page? This could be an alternative if it is only for viewing on a screen.

Can you share an example of a worksheet that looks good?

@Rouben Rostamian  

Maybe you can share parameters of your animation. I have tried to reproduce the logarithmic (is it?) spiral of the OP with MapleSim but there is something wrong my interpretations of the worksheet (or the rotating ticks are fixed on the ground which would then mean that the spiral I get is a superposition of the logarithmic spiral and the rotation of the disc).

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