Start an example with 2021 England commutes. It doesn't quite run yet.

examples/edinburgh/config.json

@@ -4,7 +4,9 @@
     "pattern": {
       "BetweenZones": {
         "zones_path": "zones.geojson",
-        "csv_path": "od.csv"
+        "csv_path": "od.csv",
+	"origin_zone_centroid_fallback": false,
+	"destination_zone_centroid_fallback": false
       }
     },
     "origins_path": "buildings.geojson",

examples/england_2011_home_to_work/config.json

@@ -4,7 +4,9 @@
     "pattern": {
       "BetweenZones": {
         "zones_path": "zones.geojson",
-        "csv_path": "od.csv"
+        "csv_path": "od.csv",
+	"origin_zone_centroid_fallback": false,
+	"destination_zone_centroid_fallback": false
       }
     },
     "origins_path": "buildings.geojson",

examples/england_2021_home_to_work/README.md

@@ -0,0 +1,11 @@
+# 2021 England home-to-work
+
+- Origins: all buildings
+- Destinations: all buildings (for now)
+- Flows include all modes (including work-from-home)
+
+Data sources:
+
+- [ODWP01EW](https://www.nomisweb.co.uk/sources/census_2021_od): UK OA to OA, about 9 million rows
+  - There are [major caveats](https://www.ons.gov.uk/peoplepopulationandcommunity/populationandmigration/populationestimates/bulletins/origindestinationdataenglandandwales/census2021#origin-destination-workplace-data) with OD data from 2021 due to COVID.
+- OA zone geojson from ONS Geography

examples/england_2021_home_to_work/config.json

@@ -0,0 +1,18 @@
+{
+  "requests": {
+    "description": "2021 home to work trips in England, for any mode of commuting. From OA-level data from ODWP01EW. Origins and destinations are all buildings.",
+    "pattern": {
+      "BetweenZones": {
+        "zones_path": "zones.geojson",
+        "csv_path": "od.csv",
+	"origin_zone_centroid_fallback": true,
+	"destination_zone_centroid_fallback": true
+      }
+    },
+    "origins_path": "buildings.geojson",
+    "destinations_path": "buildings.geojson"
+  },
+  "cost": "Distance",
+  "uptake": "Identity",
+  "lts": "BikeOttawa"
+}

examples/england_2021_home_to_work/setup.py

@@ -0,0 +1,82 @@
+import csv
+import json
+import os.path
+import sys
+
+from utils import *
+
+
+def makeOSM():
+    download(
+        url="https://download.geofabrik.de/europe/great-britain/england-latest.osm.pbf",
+        outputFilename="input/input.osm.pbf",
+    )
+
+
+def makeOrigins():
+    extractCentroids(
+        osmInput="input/input.osm.pbf", geojsonOutput="input/buildings.geojson"
+    )
+
+
+def makeDestinations():
+    # Same as origins
+    pass
+
+
+def makeZones():
+    download(
+        url="https://github.com/dabreegster/uk-boundaries/raw/main/2021_output_areas.geojson.gz",
+        outputFilename="input/zones.geojson.gz",
+    )
+    run(["gunzip", "input/zones.geojson.gz"])
+
+    with open("input/zones.geojson") as f1:
+        gj = json.load(f1)
+        gj["features"] = list(
+            filter(lambda f: f["properties"]["OA21CD"][0] == "E", gj["features"])
+        )
+        for f in gj["features"]:
+            props = {"name": f["properties"]["OA21CD"]}
+            f["properties"] = props
+
+        with open("input/zones.geojson", "w") as f2:
+            f2.write(json.dumps(gj))
+
+
+def makeOD():
+    download(
+        url="https://www.nomisweb.co.uk/output/census/2021/odwp01ew.zip",
+        outputFilename="input/odwp01ew.zip",
+    )
+    run(["unzip", "input/odwp01ew.zip", "-d", "input"])
+    with open("input/ODWP01EW_OA.csv") as f1:
+        with open("input/od.csv", "w") as f2:
+            writer = csv.DictWriter(f2, fieldnames=["from", "to", "count"])
+            writer.writeheader()
+
+            for row in csv.DictReader(f1):
+                zone1 = row["Output Areas code"]
+                zone2 = row["OA of workplace code"]
+                if zone1[0] == "E" and zone2[0] == "E":
+                    # Ideally there'd be a split by commute mode. This dataset
+                    # includes work-from-home, but just include all trips.
+                    count = int(row["Count"])
+                    if count > 0:
+                        writer.writerow(
+                            {
+                                "from": zone1,
+                                "to": zone2,
+                                "count": count,
+                            }
+                        )
+
+
+if __name__ == "__main__":
+    checkDependencies()
+    run(["mkdir", "-p", "input"])
+    makeOSM()
+    makeOrigins()
+    makeDestinations()
+    makeZones()
+    makeOD()

examples/england_2021_home_to_work/utils.py

@@ -0,0 +1 @@
+../utils.py

examples/lisbon/config.json

@@ -4,7 +4,9 @@
     "pattern": {
       "BetweenZones": {
         "zones_path": "zones.geojson",
-        "csv_path": "od.csv"
+        "csv_path": "od.csv",
+	"origin_zone_centroid_fallback": false,
+	"destination_zone_centroid_fallback": false
       }
     },
     "origins_path": "buildings.geojson",

examples/run_all.sh

@@ -59,6 +59,7 @@ run_example lisbon
 
 # Huge
 run_example england_2011_home_to_work
+run_example england_2021_home_to_work
 run_example seattle
 
 python3 summarize_results.py */output/metadata.json

od2net/src/config.rs

@@ -45,6 +45,10 @@ pub enum ODPattern {
         /// Path to a CSV file that must have 3 columns "from", "to", and "count". The first
         /// two must match zone names. "count" must be an integer.
         csv_path: String,
+        /// If an origin zone doesn't have any matching origin points, use the zone's centroid instead.
+        origin_zone_centroid_fallback: bool,
+        /// If a destination zone doesn't have any matching origin points, use the zone's centroid instead.
+        destination_zone_centroid_fallback: bool,
     },
     ZoneToPoint {
         /// Path to a GeoJSON file containing Polygons and MultiPolygons with a "name" property

od2net/src/od.rs

@@ -83,6 +83,8 @@ pub fn generate_requests(
         ODPattern::BetweenZones {
             zones_path,
             csv_path,
+            origin_zone_centroid_fallback,
+            destination_zone_centroid_fallback,
         } => {
             let zones_path = format!("{input_directory}/{zones_path}");
             let csv_path = format!("{input_directory}/{csv_path}");
@@ -91,9 +93,14 @@ pub fn generate_requests(
             let zones = load_zones(&zones_path)?;
             timer.stop();
             timer.start("Matching points to zones");
-            let origins_per_zone = points_per_polygon("origin", origins, &zones, false)?;
-            let destinations_per_zone =
-                points_per_polygon("destination", destinations, &zones, false)?;
+            let origins_per_zone =
+                points_per_polygon("origin", origins, &zones, *origin_zone_centroid_fallback)?;
+            let destinations_per_zone = points_per_polygon(
+                "destination",
+                destinations,
+                &zones,
+                *destination_zone_centroid_fallback,
+            )?;
             timer.stop();
 
             timer.start(format!("Generating requests from {csv_path}"));