Compute a a difference between two azimuth using angular math

See this slide deck where Bryan pulled this formula from: http://webspace.ship.edu/pgmarr/Geo441/Lectures/Lec

azimuth_difference(azi_1, azi_2)

Arguments

azi_1	First azimuth in decimal degrees
azi_2	Second azimuth in decimal degrees

Value

Difference in decimal degrees

Examples

azimuth_difference(355,10)
#> [1] 15