## 470 Reputation

7 years, 251 days
Maple is to me difficult. The first version I bought was Maple9, and it was more than 15 years ago. But, I couldn't use it, feeling it too difficult. But, three years ago, I thought Maple might be helpful to my study, and since then, I have continued to learn Maple. As I got able to read the Maple help, I think that I could get to use maple better now than before. But, I feel that I am a beginner yet.

## subs as well does not work...

restart;
x := a=0:  y := b=0:
subs(a=0, x or y);

false

So, subs, which has only a function of incerting something,  as well as eval does not work, and

## Thank you...

@Carl Love
Thank you for your explanation of the meaning of "situations where something mathematical happens to e."
On the other hand, I understands what kind of outcome applears through using subs: first subs works so that
the 0 is inserted into x's inDiff(sin(x),x), before Diff(sin(x),x) is calculated.

@Carl Love

Then, what do you think is the problem of VV?
I'm glad if you explain it.

## Thank you....

I couldn't understand what you are writing in 1. So, I am very happy if you show me an example
where something mathematical happens to e that has me feel it better to use eval rather than subs.

## Preference->Display->Typesetting level->...

@Preben Alsholm

For the problem of _EXPSEQ appearing at solve(x^2-1,x),
with "interface(typesetting=standard)" as you write, that problem is avoided, which is similarly done with
switching from Extended to Maple standard at Preference->Display->Typesetting level.
Thank you for your suggestion. But,  the problem you write of _EXPSEQ(1,-1) not being changed occurrs to me as well.

## @Rouben Rostamian  @Carl LoveI used...

I used Rouben's mw.mw and ascertained that Build IDs match with each other.
And, with pretty print, the same thing as to Rouben applies to me.

## Is "D(x) always returns 0" true on the ...

```f := proc (x) options operator, arrow, function_assign; piecewise(x < 0, 3^(-(1/3)*x^2), .5*2^(5^(-x))) end proc;
R(x) := int(f(t), t = x .. x+l):
L(x) := int(f(t), t = x-l .. x):
D(x) := (R(x)-L(x))/(R(x)+L(x));
eval(D(x),{l=3,x=5});```

returns

`-0.28372415e-2+0.*I`

, not zero with my mape2017 of mac.

## I calculated again...

Though your plane in R^3: 2*x+3*y-z=4 is not the same as that of op: 2*x-3*y+z = 4.
But, I think that it is because you tried to show me that there is a case that the answer
is not a plane, but a line.

Surely, in
<-9,-15,24>*x + <-12,-20,32> * y +  <20,32,-52>,

<-9,-15,24> and <-12,-20,32> are on the same line. So, in this case, the original plane degenerates
to a line pararel to <-9,-15,24>.

Thank you for teaching me a lot.

## Thank you...

Thank you.
I was trying to find a help page which will help me in having some knowledge about
how to handle arrays, for example how to change

C1 := [111, 112, 121, 122, 211, 212, 221, 222]
to
C2 := [111, 211, 121, 221, 112, 212, 122, 222].

That is, I wondered how I can change array to rtable in C_order, which is 1 dimensional, then again change it to array, and then change it to 1 dimensional rtable in Fortran_order.
I thought the help page you kindly taught me might help in such purposes.

## Thank you...

@Carl Love

Thank you Carl,
After reading what you wrote to me, I again thought that Maple is very interesting.
There are lot of things yet I haven't heard yet.
Thank you for having me notice those things.

And, I'm sorry for having forgotten to check the Voteup.

## Thank you...

@Carl Love

Thank you for your teaching me a lot.
I hadn't noticed how data of Array and Matrix was stored in a computer as the rtable,
before I read what you kindly wrote to me above.

## Thank you...

Thank you for your detailed explanation.
As for as long as what you wrote, I could digest it well.

But, on the other hand, there are other things I couldn't understand in the result of the original code of
showstat(`convert/list` :: convert_rtable_to_nested_list);
That is,  its part of

```elif rtable_num_dims(rt) < dim then
3       return rt[args[3 .. nargs]]
else
4       return [seq(procname(rt,dim+1,args[3 .. nargs],i),i = `if`(rtable_num_dims(rt) = 1,rtable_dims(rt),rtable_dims(rt)[dim]))]
end if```

Though I can guess that dim corresponds to your 2, then I can't understand why 2 is alloted to dim.
And, what is "args[3 .. nargs]" there? I understand the grammar of args[3..nargs] in itself, but
I don't understand why and how it is used in the present context.

And, firstly, I can't understand why "convert_rtable_to_nested_list", which means a property following double collon"::"  in

````convert/list` in showstat(`convert/list` :: convert_rtable_to_nested_list);
```

, can be, in turn, a procedure name which is shown in the contents of the result of the code

` showstat(`convert/list` :: convert_rtable_to_nested_list);`

like

`convert_rtable_to_nested_list := proc(rt, dim).`

And, then, I can't understand why, for example,

`convert_rtable_to_nested_list(A,3)`

does not work to bring some meaningful result other than convert_rtable_to_nested_list(the contents of A,3), though I just alloted the argument of (A, 3) to that procedure.

So, I will appreciate very much if you think further that you will teach me about these things.
But, I might be begging you too much.

## Please explain the order attribute of A ...

By the way, what is the order attribute you mention.
I will appreciate if you give an example.

## Sorry...

I sometimes feel that my ability on understanding anything is not so much.
In this case as well, I cannot find any essential distinctions except for comma between numbers.

To me CC and DD looks the same basically.

 1 2 3 4 5 6 7 Last Page 2 of 22
﻿