Import High Resolution DEM (2)

We are talking about more general case here: DEM is processed in ArcGIS (e.g. Mosaic, Extract by Mask, etc.). And it is ready for computation in Mathematica. The DEM can be exported as Float32 format, imported with the procedure in the previous post.
In this post, the DEM is exported as ARCGrid ASCII format, the whole DEM is in one text file.

data = Import["DEM.txt", {"Lines", All}];
(* the first lines are metadata *)
meta = data[[1 ;; 6]]

{"ncols 1703", "nrows 1200", "xllcorner
-86.528233463385", "yllcorner 41.430023494444", "cellsize
0.00027777777779994", "NODATA_value -9999"}

(* drop the metadata *)
data = Drop[data, 6];
(* convert string to data *)
data = Map[ToExpression, StringSplit[#]] & /@ data;

The next step is that we will make the output of ReliefPlot match the other geographic data.

1. Deal with NOData: PlotRange->{zMin,zMax}

2. Put the image into right geographic zone: DataRange-> {{Lon_Min, Lon_Max}, {Lat_Min, Lat_Max}}

ReliefPlot[data, DataReversed->True, DataRange-> {{-86.5282, -86.0552}, {41.4300, 41.7634}}, PlotRange -> {199.0, 283.0}]

Then tested it with the map created in another post.


Note: ReliefPlot needs an option: NoData->{}