Topics - Project 4 Week 1
The first week of our final project was spent learning Quantum GIS (QGIS) and about Food Deserts. Part A taught how to use QGIS by adding layers, setting a coordinate reference system, clipping layers, and grouping layers in the main window. Grouping the layers allows for multiple frames in the Print Composer, QGIS' Layout View. Just as in ArcMap's Layout View, Print Composer is where map elements, such as legends, scale bars, etc., are added. Unlike ArcMap, the data frames in QGIS must be locked if they are not being manipulated or what is done in one frame will affect what is in another. This was less of a problem in Part A than it was in Part B.
In Part B the layers were grouped by the results of our analyses. Using the census tracts of Escambia County a study area was created, then created centroids for those polygons. Using the Join tool in the
Study Area layer a join with the Near.csv file was performed to add the NEAR_DIST field from that table to the Study area attribute table. From this field we were able to create selection sets for those census groups that were within and those that were without Food Deserts. Statistics were done on each of these layers to determine the percent of the population that fell into each category. With the statistics done the layers were duplicated where necessary and grouped for their different data frames. In this second map there were more layers to contend with and forgetting to turn layers on and off in the main window and lock and unlock the data frames in the Print Composer window resulted in a lot of repetitive steps. But in the end it all came out right. Except I still haven't figured out how to put a neatline around the entire map.
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