Question

I’m trying to iteratively traverse the United States in 1 mile increments using latitude and longitude coordinates. Essentially, once I start (lets say in Portland, OR), I want to move south in one mile increments until I reach the southernmost boundary of the United States that is of the same latitude as Portland, OR. At this point, I want to start back at the northernmost part and move one mile east, repeating the entire process until I get to the east coast. I need to aggrigate these longitude/latitude points in a database.

My question is: Is it accurate to step through latitude and longitude by calculating the next lat/long pair using a delta of 1 mile each time, or are there simpler and more elegant methods to achieve my end goal?

Answer 1

I suppose you could start with the lat/lon of Portland, OR and the lat/lon of the bottom boundary. Compute the distance using Haversine found here: http://www.movable-type.co.uk/scripts/latlong.html

Using the distance above, loop through each mile using a the section Destination point given distance and bearing from start point from the website above. For moving south, your bearing will 180 deg (use π in the formula as they expect radians). For moving east, your bearing will be 90 deg (π/2).