Changes between Version 235 and Version 236 of UserGuidelines/GIS/Data

Timestamp:

06/04/14 14:02:30 (12 years ago)

Author:

Fran Boon

Comment:

--

UserGuidelines/GIS/Data

@@ -347 +347 @@
 Global Rural-Urban Mapping Project, version 1 (GRUMPv1) is a newer dataset which combines satellite with census data to locate people within settlements rather than just administrative areas:
  * http://sedac.ciesin.columbia.edu/gpw/aboutus.jsp
+
+==== US Census ====
+For the US, data is available down to block level:
+
+http://factfinder2.census.gov/faces/nav/jsf/pages/download_center.xhtml
+Dicennial Census
+2010 SF1 100% Data
+
+Convert data from NAD83 to WGS84 (e.g. using qGIS)
+
+{{{
+su postgres
+cd /data/Census2010BlockGroup
+shp2pgsql -s 4326 -I tl_2010_06037_bg10_WGS84.shp public.Census2010BlockGroup | psql -d gis
+psql
+\c gis
+ALTER TABLE census2010blockgroup ADD COLUMN population integer;
+ALTER TABLE census2010blockgroup ADD COLUMN population_density integer;
+\q
+exit
+
+w2p
+%autoindent
+pop_dict = {}
+input = os.path.join("/", "home", "data", "Census2010BlockGroup", "DEC_10_SF1_P1_with_ann.csv")
+inputFile = open(input, "r")
+header = 2
+for line in inputFile:
+    if header:
+        header -= 1
+        continue
+    parts = line.split(',', 6)
+    geoid = parts[1]
+    pop = int(parts[6].strip())
+    pop_dict[geoid] = pop
+
+inputFile.close()
+from __future__ import division
+db_string = "postgres://gis:GIS@localhost:5432/gis"
+db2 = DAL(db_string, migrate_enabled = False)
+table = db2.define_table("census2010blockgroup", Field("gid", "id"), Field("geoid10"), Field("aland10", "integer"), Field("population", "integer"), Field("population_density", "integer"), migrate=False)
+rows = db2().select(table.geoid10, table.aland10)
+for row in rows:
+    data = {}
+    geoid10 = row.geoid10
+    population = pop_dict.get(geoid10)
+    if population:
+        data["population"] = population
+        aland10 = row.aland10
+        if aland10:
+            area = aland10 / 2589988
+            population_density = population / area
+            data["population_density"] = population_density
+        db2(table.geoid10==geoid10).update(**data)
+
+db2.commit()
+}}}
+
+Can also have the Tract-level data for lower zoom (9-15) & create a Layer Group to serve the 2 layers with a style which shows only 1 level at each zoom
 === Topographic Maps ===
 ==== WMS ====