Dear all,

I have 3 sets of data - the first is 565,000 gridpoint observations of rainfall, with latitude and longitude and date, the second dataset is 700k gridpoint observations of temperature, latitude and longitude and also date . My third dataset has data on centroids of districts within states, 76 districts within 5 states.

I wish to use the geodist function to find the distance between each gridpoint (565,000 / 700,000 ) and each district (76).

My purpose of doing this is so that I can find out which gridpoint is within 100km of the district centroid, and then finally merge/collapse into a coherent panel dataset where i can calculate weighted average daily rainfall

Each dataset looks like this

Latitude Longitude Rainfall year month day edate

Latitude Longitude Temperature year month day edate

Statename Districtname District ID centroidlatitude centroidlongitude

Would appreciate ideas on how this can be done efficiently, and how to go about it (a mix of collapse, merge and geodist)

Thanks.