Hello all,

This will hopefully be a quick and easy answer. I am having some difficulties with multiple lists that have certain characteristics, so what do I have:

4 lists, all the same length that signify: [row] [coumn] [VAR1] [VAR2]

So basically I have 2 variables at each location (row,col) within a larger dataset. What I need to do is find everywhere where row and column are the same, and where they are the same, add up all of VAR1 and VAR2. [row and column are actually lat lon locations, and where I have multiple data points at the same location, I want to sum all of Var1 and all of VAR2]

I am not posting any code because I am hoping that there is a simple python function that I simply dont know about, plus the code is hundreds of lines long and it would be difficult to condense into something easily digestible. I have written some basic trys, but because they lists are so long, it slows to a snails crawl and is basically useless. I have tried various loops and permutations, but they are all too slow. Any Ideas? Thanks!

-bk