I have approx 170,000 unique integers that map to 2,000 unique integers. I want to be able to query each of the 170,000 integers to get its matching value in the list of 2,000.
What's the best container in R to do this with? I'm fine paying a high price of creating the object as long as lookups are fast.
Yes it seems like the data.table solution works well. I didn't experiment with a hash table though. It turns out I only have 13,000 unique values on the LHS after filtering so its manageable.