Symbols need not be declared in Mathics3, they can just be entered and remain variable:
x
Basic simplifications are performed:
x + 2 x
Symbols can have any name that consists of characters and digits:
iAm1Symbol ^ 2
You can assign values to symbols:
a = 2
a ^ 3
a = 4
a ^ 3
Assigning a value returns that value. If you want to suppress the output of any result, add a ; to the end of your query:
a = 4;
Values can be copied from one variable to another:
b = a;
Now changing a does not affect b:
a = 3;
b
Such a dependency can be achieved by using “delayed assignment” with the := operator (which does not return anything, as the right side is not even evaluated):
b := a ^ 2
b
a = 5;
b