' List[ Conditional statement ] ' What is this code supposed to do.

[ichabod801]

y == yi evaluates to a boolean value (True or False). But bools are actually a subclass of int, so True = 1 and False = 0. So if y == yi, it selects X[1], and if y != yi it selects X[0].

There was a ternary expression added to Python to avoid this sort of code, so that could be rewritten as:

Xi = X[1] if y == yi else X[0]