MaplePrimes - answers and comments on Question, How can I introduce an abbreviation of derivatives?

for example

Axel Vogt — Fri, 16 Nov 2012 15:53:17 Z

A function does not have a variable with a specific name, no? Just think of 'sin'.

Perhaps the following helps

  U:= (n,u) -> (D@@n)(u);

  U(2,sin)(x);
                               -sin(x)

Along that line you should find a notation, which is convenient for you.

2D Math?

acer — Fri, 16 Nov 2012 17:45:00 Z

If you don't need them marked up especially as 2D Math input then you might just be able to use the alias command, or pdetools[declare].

Here are two posts that relate to 2D Math input forms: one, and two.

acer

abbreviation of derivatives

Alejandro Jakubi — Sat, 17 Nov 2012 09:40:34 Z

For short input of derivatives (and long output), diff_table may become handy:

with(PDEtools, diff_table):
U := diff_table(u(x)):
U[x];
                                    d
                                    -- u(x)
                                    dx
U[]*U[x,x];
                                     / 2      \
                                     |d       |
                                u(x) |--- u(x)|
                                     |  2     |
                                     \dx      /

See ?PDEtools,diff_table. On the other hand declare, already mentioned by acer, is for short output (and long input) of those derivatives. You may also find useful looking at ?PDEtools,ToJet and family.

Thank you very much for your help

yihezhi — Sat, 17 Nov 2012 23:40:07 Z

Thank you very much for your help. I am studying the solutions that you provided. The two references “Subscripts as Partial Differentiation Operators” and “programming subscripted partial differentiation operators” Look very helpful