Rhyscitlema Calculator is an application to evaluate expressions expressed in the Rhyscitlema Function Expression Text (RFET) language. RFET enables the representation of mathematical expressions in plain text in simple and effective ways.
Instead of only thinking of a single-value, vector or matrix, the fully general value-structure is used: an example is (1,(2,3,4),5). RFET enables evaluating simple expressions such as 1+1 , to evaluating advanced expressions such as 2*f(3); f(x)=4x , to evaluating highly complex expressions in an Object-Oriented Programming model (using inheritance and encapsulation).
You can simply evaluate "4*5". Now suppose you later want a few more of the form 4*X, in that case you evaluate say "4*(5, 6, 7, 8)". Suppose you later want to also use 2 and 3 besides 4. In that case you evaluate say "f(2), f(3), f(4) ; f(x)=x*(5, 6, 7, 8)". The result will be a 3-by-4 matrix. Suppose you later want to keep the current result but also evaluate with the vector (50, 61, 72, 83). In that case you evaluate f(2,a), f(3,a), f(4,a), f(2,b), f(3,b), f(4,b) ; f(x,y) = x*y ; a = (5, 6, 7, 8) ; b = (50, 61, 72, 83) ; The result will be a 6-by-4 matrix.
The expression can get even more complex. But then you can always structure it effectively, thereby making evaluation a lot easier than ever! You can even make it vary with time and just watch, or make it be updated upon button presses. You can build an entire RFET script and save for future re-use.