For common operators like + the inverse is −, and × it is ÷. Wondering if a "search" or "filter" on a set can have an inverse.
B={a∈Z∣a<10∧a>5}
That's a super simple search but it demonstrates the point. The inverse of a search is something like a "non-search" perhaps, but that doesn't quite make sense. A "forget" maybe. The inverse doesn't seem like search for everything "except", such as:
B−1={a∈Z∣a≥10∨a≤5}
If you are trying to "undo" a search, it seems like you just don't want to perform any search. Wondering what your thoughts are on this type of operation. The operation might look like:
Z∘{a∈Z∣a<10∧a>5}={6,7,8,9}
I don't know what the inverse would look like, maybe:
{a∈Z∣a<10∧a>5}∘{a∈Z∣a<10∧a>5}−1=Z
Or perhaps in this case, there just isn't an inverse :/. If not, wondering why certain things can't have an inverse.
Answer
Your concept of "search or "filter" is somewhat like intersection of sets. That is, if A is a search space and B represents a condition or criterion, then C:=A∩B represents the "search" or "filter" result. However, this clearly does not have an inverse. That is you can't recover A from C, the intersection even if you know B. It would be a lot easier to "keep a backup" of A instead.
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