Question

I’m trying to represent boolean expressions in sum of products form(SOP) in Python with only lists.

For example, I have boolean expression

ABC+DE(FG+IH)

I need to find a list equivalent of the expression above, so by reading the list or nested list and following certain rules to read the list, the program/programmer reading the list will be able to convert it back to the boolean expression.

One way I thought of doing this is constructing nested lists. Two rules to follow:

1. elements in the same list are ANDed together
2. lists are parallel to each other, therfore ORed together.

So for the example above, it will translate to:

[[A,B,C],[D,E,[[F,G],[I,H]]]]

But this set of rules conflicts itself in some cases. For example, given [[E,F],[D,C]], it can either mean EF+DC or EFDC, as [E,F] and [D,C] are in the same list so they should be anded, but lists are parallel so they should be ORed too.

I feel like I need to set some precedence between the 2 rules above, or add another rule to make it more clear.

Any thoughts or suggestions are welcome. Also it’s not homework, just something for fun.
Thanks in advance!!

Answer 1

You could go the LISPy route and have the first item in each list be the operator. For example, the expression you gave

ABC+DE(FG+IH)

would become

['or', ['and', A, B, C], ['and', D, E, ['or', ['and', F, G], ['and', I, H]]]]

Which is pretty readable, considering. Cheers!