This is NOT about importing/exporting Excel data to/from Mathematica.
This is purely a UI question.
The Mathematica notebook interface is very "linear" — I type in an input cell and Mathematica produces an output cell. Is it possible to implement something like an Excel interface for Mathematica?
For example, if I have:
cell
a1 = "x+y"cell
b1 = "x-y"cell
c1 = "= a1^2 + b1^2"
Then, Mathematica puts "2(x^2+y^2)" into c1. If I modify a1 to say "3", Mathematica puts "(x-y)^2 + 9" into c1.
