Merge pull request #89 from GenericMappingTools/fix-some-indices

Fix NDWI and a couple other indices that were wrong. Needed to X -1

Author: joa-quim

src/grid_at_sensor.jl

@@ -167,6 +167,8 @@ function helper_find_sds(sds::String, info::String, ind_EOLs::Vector{UnitRange{I
 				((ind = findfirst(":lat", info)) === nothing) && (odeusse = true)
 			elseif (startswith(sds, "lon"))
 				((ind = findfirst(":lon", info)) === nothing) && (odeusse = true)
+			else
+				odeusse = true
 			end
 		end
 		odeusse && error("The band name -- " * sds * " -- does not exist")
@@ -241,7 +243,7 @@ function get_lon_lat_qual(sds_lon::String, sds_lat::String, qual, inc)
 	(inc[1] == 0.0) && (dx = diff(G.z[:, round(Int, size(G.z, 1)/2)]); dx = dx[dx .< 10])
 	lon = G.z[qual]
 	G = gd2gmt(sds_lat);
-	(inc[2] == 0.0) && (dy = diff(G.z[round(Int, size(G.z, 2)/2), :]); dy = dy[dy .< 10])
+	(inc[2] == 0.0) && (dy = diff(G.z[round(Int, size(G.z, 1)/2), :]); dy = dy[dy .< 10])
 	lat = G.z[qual]
 	return lon, lat, dx, dy
 end

src/spectral_indices.jl

@@ -693,15 +693,18 @@ function sp_indices(bnd1, bnd2, bnd3=nothing; index::String="", kwargs...)
 		# NDBI, LSWI. Normalized difference water index. Gao 1996, Chen 2005; NDWI2 => (nir - swir2)/(nir + swir2)
 		# Normalized difference red edge index. Gitelson and Merzlyak 1994; (redEdge2 - redEdge1)/(redEdge2 + redEdge1)
 		# Normalized difference red edge index 2. Barnes et al 2000; (redEdge3 - redEdge1)/(redEdge3 + redEdge1)
+
+		# Need to swap bnd1 and bnd2 for indices that are defined as (shorter_cdo - longer_cdo)
+		_b1, _b2 = (index == "MNDWI" || index == "NBRI" || index == "NDWI" || index == "NDWI2" || index == "NDWI2") ? (bnd2, bnd1) : (bnd1, bnd2)
 		if (ismask)
 			@inbounds Threads.@threads for k = 1:mn
-				t1 = bnd1[k]*i_tmax;	t2 = bnd2[k]*i_tmax
+				t1 = _b1[k]*i_tmax;	t2 = _b2[k]*i_tmax
 				t = (t2 - t1) / (t1 + t2)
 				(fcomp(t, threshold) && t <= 1) && (mask[k] = 255)
 			end
 		else
 			@inbounds Threads.@threads for k = 1:mn
-				t1 = bnd1[k]*i_tmax;	t2 = bnd2[k]*i_tmax
+				t1 = _b1[k]*i_tmax;	t2 = _b2[k]*i_tmax
 				t = (t2 - t1) / (t1 + t2)
 				(t >= -1 && t <= 1) && (img[k] = t)
 			end