geo-l1-cairo-multipoint-hull
Map (reference ← swipe → agent)
0:00
I'm putting together the accessibility report for the Metro, and its static maps need to show how far each station's underground box reaches at street level. `cairo_metro_stations.geojson` has each station's street-level entrances. Can you compute the convex hull of each station's entrances and save the result to `cairo_metro_hulls.geojson`, one Polygon per station? Every row must carry `station_name_en` and `station_name_ar`, both non-empty, with the original Arabic strings and diacritics preserved exactly as they appear in the input.
0:00
System info
{
"adapter": "openrouter",
"model": "deepseek/deepseek-v4-flash",
"base_url": "https://openrouter.ai/api/v1"
}
0:02
Let me start by reading the input file to understand its structure.
0:02
Read
/work/cairo_metro_stations.geojson
1 {
2 "type": "FeatureCollection",
3 "name": "cairo_metro_stations",
4 "crs": { "type": "name", "properties": { "name": "urn:ogc:def:crs:OGC:1.3:CRS84" } },
5 "features": [
6 { "type": "Feature", "properties": { "station_name_en": "Al-Shohadaa", "station_name_ar": "الشهداء" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.246441, 30.063109 ], [ 31.246778, 30.062428 ], [ 31.246859, 30.063158 ], [ 31.247736, 30.061538 ], [ 31.247931, 30.062636 ] ] } },
7 { "type": "Feature", "properties": { "station_name_en": "Attaba", "station_name_ar": "العتبة" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.246196, 30.051508 ], [ 31.246396, 30.051849 ], [ 31.246716, 30.051944 ], [ 31.246936, 30.052384 ], [ 31.247559, 30.052018 ] ] } },
8 { "type": "Feature", "properties": { "station_name_en": "Cairo University", "station_name_ar": "جامعة القاهرة" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.200216, 30.025256 ], [ 31.200826, 30.026512 ], [ 31.201257, 30.02592 ], [ 31.201463, 30.025147 ], [ 31.20167, 30.026648 ] ] } },
9 { "type": "Feature", "properties": { "station_name_en": "Dokki", "station_name_ar": "الدقي" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.211926, 30.038446 ], [ 31.212858, 30.038563 ], [ 31.213071, 30.039014 ], [ 31.213408, 30.037575 ] ] } },
10 { "type": "Feature", "properties": { "station_name_en": "El Demerdash", "station_name_ar": "الدمرداش" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.272726, 30.079096 ], [ 31.272841, 30.079167 ], [ 31.273817, 30.078925 ], [ 31.274032, 30.079479 ] ] } },
11 { "type": "Feature", "properties": { "station_name_en": "El Malek El Saleh", "station_name_ar": "الملك الصالح" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.233442, 30.019095 ], [ 31.233473, 30.018682 ], [ 31.234504, 30.017367 ], [ 31.234545, 30.017379 ] ] } },
12 { "type": "Feature", "properties": { "station_name_en": "El-Marg", "station_name_ar": "المرج" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.334217, 30.146468 ], [ 31.334253, 30.146538 ], [ 31.334782, 30.146493 ] ] } },
13 { "type": "Feature", "properties": { "station_name_en": "Ghamra", "station_name_ar": "غمرة" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.263164, 30.068985 ], [ 31.263197, 30.068259 ], [ 31.264394, 30.068864 ] ] } },
14 { "type": "Feature", "properties": { "station_name_en": "Hadayek El-Zaitoun", "station_name_ar": "حدائق الزيتون" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.3063, 30.122913 ], [ 31.30776, 30.123157 ], [ 31.307789, 30.122103 ], [ 31.307849, 30.12264 ] ] } },
15 { "type": "Feature", "properties": { "station_name_en": "Helmeyet El-Zaitoun", "station_name_ar": "حلمية الزيتون" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.302031, 30.11224 ], [ 31.302815, 30.111791 ], [ 31.303183, 30.111908 ] ] } },
16 { "type": "Feature", "properties": { "station_name_en": "Helwan", "station_name_ar": "حلوان" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.333401, 29.847533 ], [ 31.333518, 29.84856 ], [ 31.33383, 29.849118 ], [ 31.33423, 29.849025 ] ] } },
17 { "type": "Feature", "properties": { "station_name_en": "Maadi", "station_name_ar": "المعادي" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.256977, 29.960391 ], [ 31.256996, 29.961004 ], [ 31.25776, 29.95986 ], [ 31.25825, 29.959814 ], [ 31.258343, 29.961018 ] ] } },
18 { "type": "Feature", "properties": { "station_name_en": "Manshiet El-Sadr", "station_name_ar": "منشية الصدر" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.286919, 30.07915 ], [ 31.287036, 30.078534 ], [ 31.287853, 30.078947 ] ] } },
19 { "type": "Feature", "properties": { "station_name_en": "Mar Girgis", "station_name_ar": "مار جرجس" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.229596, 30.005582 ], [ 31.230357, 30.006424 ], [ 31.230863, 30.006943 ] ] } },
20 { "type": "Feature", "properties": { "station_name_en": "Mohamed Naguib", "station_name_ar": "محمد نجيب" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.245937, 30.043448 ], [ 31.246011, 30.042638 ], [ 31.246072, 30.042795 ], [ 31.246112, 30.043492 ] ] } },
21 { "type": "Feature", "properties": { "station_name_en": "Nasser", "station_name_ar": "عبد الناصر" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.243015, 30.052462 ], [ 31.243026, 30.053981 ], [ 31.244356, 30.052241 ], [ 31.244365, 30.053045 ] ] } },
22 { "type": "Feature", "properties": { "station_name_en": "Opera", "station_name_ar": "الأوبرا" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.223629, 30.042483 ], [ 31.22406, 30.041978 ], [ 31.224966, 30.042008 ] ] } },
23 { "type": "Feature", "properties": { "station_name_en": "Saad Zaghloul", "station_name_ar": "سعد زغلول" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.248006, 30.037688 ], [ 31.248884, 30.037798 ], [ 31.248954, 30.037359 ] ] } },
24 { "type": "Feature", "properties": { "station_name_en": "Sadat", "station_name_ar": "السادات" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.235032, 30.043948 ], [ 31.236163, 30.044623 ], [ 31.236249, 30.044071 ], [ 31.236357, 30.043795 ], [ 31.236493, 30.044874 ] ] } },
25 { "type": "Feature", "properties": { "station_name_en": "Sayeda Zeinab", "station_name_ar": "السيدة زينب" }, "geometry": { "type": "MultiPoint", "coordinates": [ [ 31.238434, 30.030095 ], [ 31.23933, 30.028708 ], [ 31.239612, 30.029943 ], [ 31.239711, 30.028807 ] ] } }
26 ]
27 }
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Let me analyze the data: 1. It's a GeoJSON FeatureCollection with features having MultiPoint geometries (station entrances). 2. Each feature has `station_name_en` and `station_name_ar` properties. 3. I need to compute the convex hull of the MultiPoint coordinates for each station, resulting in a Polygon. 4. I need to output to `cairo_metro_hulls.geojson` with the same properties. Let me write a Python script using geopandas and shapely to do this. Actually, since each feature already has MultiPoint geometry, I can compute the convex hull of each MultiPoint. Let me use geopandas to read, compute convex hull, and save. Let me check if there are stations that might have only 1 or 2 entrances - in that case convex hull might produce Point or LineString. Let me see: Looking at the data: - Al-Shohadaa: 5 points - Attaba: 5 points - Cairo University: 5 points - Dokki: 4 points - El Demerdash: 4 points - El Malek El Saleh: 4 points - El-Marg: 3 points - Ghamra: 3 points - Hadayek El-Zaitoun: 4 points - Helmeyet El-Zaitoun: 3 points - Helwan: 4 points - Maadi: 5 points - Manshiet El-Sadr: 3 points - Mar Girgis: 3 points - Mohamed Naguib: 4 points - Nasser: 4 points - Opera: 3 points - Saad Zaghloul: 3 points - Sadat: 5 points - Sayeda Zeinab: 4 points All stations have at least 3 points, so convex hull should produce a Polygon for all. If any had fewer, shapely's convex_hull would return a Point (1 point) or LineString (2 points), but that's fine - I'll handle it. Let me write the script.
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Write
/work/solve.py
content · 17 lines · py
import geopandas as gpd
from shapely.geometry import MultiPoint
# Read the input file
gdf = gpd.read_file("/work/cairo_metro_stations.geojson")
# Compute convex hull of each station's MultiPoint
# The convex_hull of a MultiPoint is a Polygon (if >= 3 distinct points)
gdf["geometry"] = gdf["geometry"].apply(lambda geom: geom.convex_hull)
# Keep only the required columns
gdf = gdf[["station_name_en", "station_name_ar", "geometry"]]
# Write to output file
gdf.to_file("/work/cairo_metro_hulls.geojson", driver="GeoJSON")
print("Done. Features written:", len(gdf))Wrote /work/solve.py (569 chars).
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Let me run the script.
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Bash
cd /work && python solve.py
Done. Features written: 20
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Let me verify the output file to make sure everything looks correct - the station names are preserved with Arabic diacritics, there are 20 features, each with a Polygon geometry.
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Read
/work/cairo_metro_hulls.geojson
1 {
2 "type": "FeatureCollection",
3 "name": "cairo_metro_hulls",
4 "crs": { "type": "name", "properties": { "name": "urn:ogc:def:crs:OGC:1.3:CRS84" } },
5 "features": [
6 { "type": "Feature", "properties": { "station_name_en": "Al-Shohadaa", "station_name_ar": "الشهداء" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.247736, 30.061538 ], [ 31.246778, 30.062428 ], [ 31.246441, 30.063109 ], [ 31.246859, 30.063158 ], [ 31.247931, 30.062636 ], [ 31.247736, 30.061538 ] ] ] } },
7 { "type": "Feature", "properties": { "station_name_en": "Attaba", "station_name_ar": "العتبة" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.246196, 30.051508 ], [ 31.246396, 30.051849 ], [ 31.246936, 30.052384 ], [ 31.247559, 30.052018 ], [ 31.246196, 30.051508 ] ] ] } },
8 { "type": "Feature", "properties": { "station_name_en": "Cairo University", "station_name_ar": "جامعة القاهرة" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.201463, 30.025147 ], [ 31.200216, 30.025256 ], [ 31.200826, 30.026512 ], [ 31.20167, 30.026648 ], [ 31.201463, 30.025147 ] ] ] } },
9 { "type": "Feature", "properties": { "station_name_en": "Dokki", "station_name_ar": "الدقي" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.213408, 30.037575 ], [ 31.211926, 30.038446 ], [ 31.213071, 30.039014 ], [ 31.213408, 30.037575 ] ] ] } },
10 { "type": "Feature", "properties": { "station_name_en": "El Demerdash", "station_name_ar": "الدمرداش" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.273817, 30.078925 ], [ 31.272726, 30.079096 ], [ 31.272841, 30.079167 ], [ 31.274032, 30.079479 ], [ 31.273817, 30.078925 ] ] ] } },
11 { "type": "Feature", "properties": { "station_name_en": "El Malek El Saleh", "station_name_ar": "الملك الصالح" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.234504, 30.017367 ], [ 31.233473, 30.018682 ], [ 31.233442, 30.019095 ], [ 31.234545, 30.017379 ], [ 31.234504, 30.017367 ] ] ] } },
12 { "type": "Feature", "properties": { "station_name_en": "El-Marg", "station_name_ar": "المرج" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.334217, 30.146468 ], [ 31.334253, 30.146538 ], [ 31.334782, 30.146493 ], [ 31.334217, 30.146468 ] ] ] } },
13 { "type": "Feature", "properties": { "station_name_en": "Ghamra", "station_name_ar": "غمرة" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.263197, 30.068259 ], [ 31.263164, 30.068985 ], [ 31.264394, 30.068864 ], [ 31.263197, 30.068259 ] ] ] } },
14 { "type": "Feature", "properties": { "station_name_en": "Hadayek El-Zaitoun", "station_name_ar": "حدائق الزيتون" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.307789, 30.122103 ], [ 31.3063, 30.122913 ], [ 31.30776, 30.123157 ], [ 31.307849, 30.12264 ], [ 31.307789, 30.122103 ] ] ] } },
15 { "type": "Feature", "properties": { "station_name_en": "Helmeyet El-Zaitoun", "station_name_ar": "حلمية الزيتون" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.302815, 30.111791 ], [ 31.302031, 30.11224 ], [ 31.303183, 30.111908 ], [ 31.302815, 30.111791 ] ] ] } },
16 { "type": "Feature", "properties": { "station_name_en": "Helwan", "station_name_ar": "حلوان" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.333401, 29.847533 ], [ 31.333518, 29.84856 ], [ 31.33383, 29.849118 ], [ 31.33423, 29.849025 ], [ 31.333401, 29.847533 ] ] ] } },
17 { "type": "Feature", "properties": { "station_name_en": "Maadi", "station_name_ar": "المعادي" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.25825, 29.959814 ], [ 31.25776, 29.95986 ], [ 31.256977, 29.960391 ], [ 31.256996, 29.961004 ], [ 31.258343, 29.961018 ], [ 31.25825, 29.959814 ] ] ] } },
18 { "type": "Feature", "properties": { "station_name_en": "Manshiet El-Sadr", "station_name_ar": "منشية الصدر" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.287036, 30.078534 ], [ 31.286919, 30.07915 ], [ 31.287853, 30.078947 ], [ 31.287036, 30.078534 ] ] ] } },
19 { "type": "Feature", "properties": { "station_name_en": "Mar Girgis", "station_name_ar": "مار جرجس" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.229596, 30.005582 ], [ 31.230357, 30.006424 ], [ 31.230863, 30.006943 ], [ 31.229596, 30.005582 ] ] ] } },
20 { "type": "Feature", "properties": { "station_name_en": "Mohamed Naguib", "station_name_ar": "محمد نجيب" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.246011, 30.042638 ], [ 31.245937, 30.043448 ], [ 31.246112, 30.043492 ], [ 31.246072, 30.042795 ], [ 31.246011, 30.042638 ] ] ] } },
21 { "type": "Feature", "properties": { "station_name_en": "Nasser", "station_name_ar": "عبد الناصر" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.244356, 30.052241 ], [ 31.243015, 30.052462 ], [ 31.243026, 30.053981 ], [ 31.244365, 30.053045 ], [ 31.244356, 30.052241 ] ] ] } },
22 { "type": "Feature", "properties": { "station_name_en": "Opera", "station_name_ar": "الأوبرا" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.22406, 30.041978 ], [ 31.223629, 30.042483 ], [ 31.224966, 30.042008 ], [ 31.22406, 30.041978 ] ] ] } },
23 { "type": "Feature", "properties": { "station_name_en": "Saad Zaghloul", "station_name_ar": "سعد زغلول" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.248954, 30.037359 ], [ 31.248006, 30.037688 ], [ 31.248884, 30.037798 ], [ 31.248954, 30.037359 ] ] ] } },
24 { "type": "Feature", "properties": { "station_name_en": "Sadat", "station_name_ar": "السادات" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.236357, 30.043795 ], [ 31.235032, 30.043948 ], [ 31.236493, 30.044874 ], [ 31.236357, 30.043795 ] ] ] } },
25 { "type": "Feature", "properties": { "station_name_en": "Sayeda Zeinab", "station_name_ar": "السيدة زينب" }, "geometry": { "type": "Polygon", "coordinates": [ [ [ 31.23933, 30.028708 ], [ 31.238434, 30.030095 ], [ 31.239612, 30.029943 ], [ 31.239711, 30.028807 ], [ 31.23933, 30.028708 ] ] ] } }
26 ]
27 }
0:24
The output looks good. Let me verify: 1. Each feature has `station_name_en` and `station_name_ar` - yes, both present. 2. Both non-empty - yes. 3. Arabic strings preserved exactly as in input - yes, I can see them matching. 4. Each geometry is a Polygon (convex hull of the MultiPoint) - yes. 5. 20 features, one per station - correct. The file is saved to `/work/cairo_metro_hulls.geojson` as requested.
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