import sys
import os
import site
-import pgdb
from optparse import OptionParser
# Basically, add '../src' to our path.
# Needed for the imports that follow.
site.addsitedir(os.path.dirname(os.path.abspath(sys.argv[0])) + '/../src')
+import Census
import Configuration.Defaults
import ExitCodes
import GPS
import StringUtils
-import SummaryFile1
"""
parser = OptionParser(usage=usage, add_help_option = False)
# Use this module's docstring as the description.
-parser.description = __doc__
+parser.description = __doc__.strip()
parser.add_option('-h',
'--host',
help='The username who has access to the database.',
default=Configuration.Defaults.DATABASE_USERNAME)
+parser.add_option('-s',
+ '--srid',
+ type="int",
+ help="SRID of the input geometry. Defaults to %s." % Configuration.Defaults.SRID,
+ default=Configuration.Defaults.SRID)
+
(options, args) = parser.parse_args()
if len(args) < 2:
coords.longitude = float(args[0])
coords.latitude = float(args[1])
-conn = pgdb.connect(host=options.host,
- database=options.database,
- user=options.username)
-
-cursor = conn.cursor()
-
-###########
-# WARNING #
-###########
-#
-# Most GIS software, including PostGIS and the associated libraries,
-# store and manipulate GPS coordinates in (longitude, latitude) format
-# rather than (latitude, longitude) format.
-#
-
-query = """
-SELECT population_density
-FROM (sf1_blocks INNER JOIN tiger
- ON sf1_blocks.tiger_blkidfp00=tiger.blkidfp00)
-WHERE ST_Contains(tiger.the_geom,
- ST_SetSRID(ST_Point(%.6f, %.6f), 4269));
-""" % (coords.longitude, coords.latitude)
-
-cursor.execute(query)
-rows = cursor.fetchall()
-
-if len(rows) > 0:
- avg_density = rows[0][0]
+cdb = Census.Database(options.host,
+ options.database,
+ options.username,
+ options.srid)
+
+avg_density = cdb.find_average_population_density(coords)
+
+if (avg_density != None):
print str(avg_density)
else:
print 'Error: No rows returned.'
print 'Did you pass (longitude, latitude) in the correct order?'
raise SystemExit(ExitCodes.NO_RESULTS)
-
-conn.close()
+