We had several tasks this week and five maps to produce. The first section I worked on was Spatial Analyst. We had to create a model to conduct spatial analysis of an elevation raster - creating slope (steepness) and hillshade (shows shadows based on elevation and orientation relative to the sun) and aspect (shows compass direction of each raster cell). ArcMap turns out to have three different ways of building such models: using the tool in ArcToolbox, which involves filling out the usual dialog box for input and output; dragging-and-dropping using the ModelBuilder (see the graphic with rectangles and ovals above), and creating the code using the command line. I would describe ModelBuilder as clunky and the command line approach as elegant, in part because the code lets you see what you're doing and ModelBuilder just says "Please do something with this input". But they all seem to work. This short lab section was relatively straightforward.
Second, we had to convert vector line and polygon files to raster files and reclassify those raster files. The largely purple graphic above shows the converted and reclassified vegetation map of a vegetation study area in/near Harlan, Kentucky. I was a bit confused because the white spaces within the study area were originally, in the vector file, "altered/developed" land; we had to reclassify this as NoData, which meant that in the reclassified raster version all that land comes out as white as well as the small portion that was NoData before (hence my note at the bottom of the map).
Third, we had to produce two maps of the Tampa, Florida area, using a variety of labels and annotation to create the map. I have used labels a little in ArcMap but never felt I knew what I was doing, so this was directly useful for me. The Cities and Roads map used different symbols for different kinds of roads; the Paddling Trails & Bird Sanctuaries map also used annotation. These maps reminded me of how tricky it can be to get all the information you need on to a map without crowding it - the Paddling Trails map of course needs roads as well as they are such an integral part of the landscape (and how else do you get to the rivers you want to paddle?) although without the roads it is prettier! I had a lot of difficulty passing the ESRI exam on the labels&annotation section; it's confusing and the only easy part was decoding the Vbscript code. I'm looking forward to the programming class.
The final map, at the top left I think, was from the 3D analyst section. It shows a hiker's-eye view of the cabin ( the red dot) and the two "observers" (the other two dots; this made me think of military/police exercises!). The black snaky lines are actually contour lines - I couldn't resist using the "Contours" icon when I found it, although I had no idea how to use it or how to remove the lines. The white contour line at the top is the last one I created, and since I didn't know how to remove it and it was the last one, it's still white. The 3D function in ArcScene was very interesting - when I wasn't frantically trying to stop the navigation tool from turning my mountains round and round - although I don't have an idea of what I could do with it in real life at this point and I do wonder how useful 3D is given what one can interpolate from 2D maps. The other thing that intrigued me greatly was seeing the overlapping transparent 3D rectangles that make up the 3D display before they had finished drawing the map completely.
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