Merge pull request #467 from WilhelmusLab/feat-julia-latlon

Fixing error in latlon.py

src/latlon.py

@@ -12,13 +12,17 @@ def getlatlon(imgpath):
     im = rasterio.open(imgpath)
     crs = im.crs.__str__()  # Coordinate reference system code
     nrows, ncols = im.shape
-    rows, cols = np.meshgrid(np.arange(nrows), np.arange(ncols))
+    cols, rows = np.meshgrid(np.arange(ncols), np.arange(nrows))
     xs, ys = rasterio.transform.xy(im.transform, rows, cols)
+    xs = np.array(xs)
+    ys = np.array(ys)
+
     # X and Y are the 1D index vectors
-    X = np.array(xs)[:, 0]
-    Y = np.array(ys)[0, :]
+    X = xs[0, :]
+    Y = ys[:, 0]
     ps_to_ll = Transformer.from_crs(im.crs, "WGS84", always_xy=True)
     lons, lats = ps_to_ll.transform(np.ravel(xs), np.ravel(ys))
+
     # longitude and latitude are 2D index arrays
     longitude = np.reshape(lons, (nrows, ncols))
     latitude = np.reshape(lats, (nrows, ncols))

test/test-latlon.jl

@@ -0,0 +1,27 @@
+using IceFloeTracker: getlatlon
+
+@testset "getlatlon" begin
+    imgpth = "test_inputs/latlon/latlon_test_image-2020-06-21T00_00_00Z.tif"
+
+    # vec needed to convert to vector instead of nx1 matrix
+    expected_X = vec(readdlm("test_inputs/latlon/X.csv", ',', Float64))
+    expected_Y = vec(readdlm("test_inputs/latlon/Y.csv", ',', Float64))
+
+    expected_lat = readdlm("test_inputs/latlon/latitude.csv", ',', Float64)
+    expected_lon = readdlm("test_inputs/latlon/longitude.csv", ',', Float64)
+
+    latlon = getlatlon(imgpth)
+    X = latlon["X"]
+    Y = latlon["Y"]
+    lat = latlon["latitude"]
+    lon = latlon["longitude"]
+
+    # round to 4 decimal places to avoid weirdness in different arch/os
+    expected_lat, expected_lon, expected_X, expected_Y = [round.(arr, digits=4) for arr in [expected_lat, expected_lon, expected_X, expected_Y]]
+    lat, lon, X, Y = [round.(arr, digits=4) for arr in [lat, lon, X, Y]]
+
+    @test expected_X == X
+    @test expected_Y == Y
+    @test expected_lat == lat
+    @test expected_lon == lon
+end