function construction - Custom Division with lists

function construction - Custom Division with lists - divide by zero

I have some lists of data that I need to divide by each-other, but my problem is that for some values the denominator is zero. Now these particular values are not very important, but I still need to keep them in the lists.

To solve my problem, I tried defining my own division function:

division[a_,b_]:=a/b

division[a_,0]=-1

This works great for single numbers,

division[52,0]
out: -1

but not for lists:

division[{1,2,0},{0,1,2}]
out: {ComplexInfinity,2,0}

How do I make my predefined output work for lists as well?

Of course, another solution to my problem would be to iterate over the list with e.g. a For loop and an If, but I think there should be a neater way of doing this.

Answer

SetAttributes[division, Listable]
division[{1, 2, 0}, {0, 1, 2}]

{-1, 2, 0}

Comments

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