27 lines
749 B
Mathematica
27 lines
749 B
Mathematica
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function [ sx, sy ] = coordinates_to_dxdy( long, lat )
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%constants
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r_earth = 6371000; %(m) earth radius
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%calc
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sx = 0;
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sy = 0;
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for n = 1:1:length(long)
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if n==1
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else
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dlong = long(n) - long(n-1); %(degrees) change in long position during this time slice
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dlat = lat(n) - lat(n-1); %(degrees) change in lat position during this time slice
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meters_per_deg_long = (2*pi/360) * r_earth * cosd(lat(n)); %(m/deg) long
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meters_per_deg_lat = (2*pi/360) * r_earth; %(m/deg) lat
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dx = meters_per_deg_long * dlong; %(m)
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dy = meters_per_deg_lat * dlat; %(m)
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sx(n) = sx(end) + dx; %m
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sy(n) = sy(end) + dy; %m
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end
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end
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end
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