1 ACCEPTED SOLUTION
Accepted Solutions
Here you are.
If you don't like to use the vector notation when you provide the arguments, you may use the stack command where you can edit the arguments more convenient.
It would be easy to write a function for your yellow expressions, but concerning your green expressions you demand too much for at least two reasons:
1) A user defined function can't have a variable number of arguments. You have to decide whether RESULT() should have two or just one argument.
2) Life would be much easier if we could agree on that the second function argument always indicates the columns in the matrix and not one time the columns and the other time one additional row. Furhermore - how should RESULT() know in the screenshot above that you mean just the firrst column?
Of course it would be possible to implement RESULT() in such a way that in case the second argument is not a valid column number but a string that it meant as an additional row indicator and column(s) should default to 1 in the special case. But I would strongly advise against that kind of (very) special rule.
So something like the following is easy to implement, but your green examples -- harder (2nd argument is row, too) up to impossibe (function with either one or more arguments).
The expressions in green, were just a curiosity. Do not know why but I came to mind if it was possible to introduce the variables that way.
It was my mistake to introduce this curiosity in the question 
. Concerning the terms in yellow, would greatly appreciate if you could help me with these expressions, because for my is difficult create a routine for that.
Here you are.
If you don't like to use the vector notation when you provide the arguments, you may use the stack command where you can edit the arguments more convenient.
So it possible enter the arguments of the two ways. 
Thank you very much Werner and also to Stuart for your suggestion.
