Implement city.py

lib/xmet/city.py

@@ -0,0 +1,41 @@
+import csv
+import shapely
+
+"""
+Implements a parser and wrapper class for the top 150 populous US cities
+available on Wikipedia:
+
+    https://en.wikipedia.org/wiki/List_of_United_States_cities_by_population
+
+The input TSV file is created by copying and pasting the tabular data
+from a web browser into a text file.
+"""
+
+class City():
+    name:         str
+    state:        str
+    pop_estimate: int
+    pop_census:   int
+    location:     shapely.Point
+
+    @staticmethod
+    def from_tsv_row(row: list):
+        city = City()
+        city.name         = row[0]
+        city.state        = row[1]
+        city.pop_estimate = int(row[2])
+        city.pop_census   = int(row[3])
+        city.location     = shapely.Point(float(row[10]), float(row[9]))
+
+        return city
+
+    @staticmethod
+    def each_from_tsv(file: str):
+        with open(file) as fh:
+            reader = csv.reader(fh, delimiter='\t')
+
+            for row in reader:
+                for i in range(0, len(row)):
+                    row[i] = row[i].rstrip()
+
+                yield City.from_tsv_row(row)