function [u, v] = sd2uv(s,d)
% sd2uv - take speed, direction and return east, north velocity components
% based on geographic coordinates (N = 0 degrees)
%
% D. Nowacki nowacki@uw.edu
    u = s .* sin(d .* pi ./ 180);
    v = s .* cos(d .* pi ./ 180);
end