zdeltakronekre fu'ivla

x1 is a Kronecker delta function defined on structure x2 which evaluates to one for any argument belonging to subset x3 and which evaluates to zero otherwise

x2 determines domain, codomain, and the meaning of "zero" and "one". x3 is a set; for the typical usage of delta(x,n) for fixed n, let x3 be the singleton set such that n is an element thereof.

In notes:

Binary mekso operator: uniform probability A(X2)u(X for input (X1,X where X1 is a number and X2 is a set or space. (See notes for details).
x1 (function) is the restriction of function x2 to domain set x3