PROCESS

This portion of the atlas is to give the user an idea as to the steps that were taken to create the maps and images of this atlas. The creator employed the program ArcGIS Desktop, specifically ArcMap and ArcScene. The two-dimensional maps were created with ArcMap, and the three-dimensional maps were created using ArcScene.

The creator began with the program ArcMap, with the shapefile of the topographic curves of the city of Valparaiso, and the shapefile of the census blocks of the city, from INE. She then went on to utilize the ArcGIS extension 3D Analyst to convert the shapefile of the curves into a raster in order to create a three-dimensional version of the map in ArcScene. The first image is of the elevation in meters of Valparaiso, and the second image is a map of the census blocks. The last, and most colorful image, is the raster created from the topographic curves.

With the program ArcScene, the creator converted the shapefiles and the raster into three-dimensional shapefiles, using the z-values which she retrieved from the topographic curves. The following maps are the three-dimensional versions of the topographic and census block maps, with a view from West to East, more or less.

In order to determine the location of the most impoverished places in Valparaiso, the creator had to find data for poverty. In the shapefile of the census blocks, there were economic data for the categories of D and E (the most impoverished, from levels A-E). A new category was created, which added the data for groups D and E for each census block. The map to the right is a color-schemed three-dimensional map of the poverty in Valparaiso, seen from above. The colors range from green to red, with the darkest green having the least amount of poverty, and the brightest red having the most.

After making the separate maps of elevation and poverty, the creator had to combine the two maps. In ArcGIS, you can create a map with various layers. There is a table of contents on the left of the screen that tells you the different layers. The layer at the top of the table of contents is displayed first, on top of the other layers. For the final map, the user is supposed to be able to see the map of poverty over the map of elevation. Therefore, the creator had to place the layer of poverty above the layer of elevation in the table of contents, as shown in the image to the left. In order to see the two maps at the same time, the creator applied a transparency to the poverty layer. This is rather easy to do, by opening the properties dialog box for the layer and clicking the display tab. There is an option for setting the transparency, and the creator changed this transparency from 0% to 50%. The two images that follow are examples of the final map, which you can see under the "RESEARCH CONCLUSIONS" entry.