dc-l2-cairo-invalid-dedup

Status: done
Score: 0.914
Duration: 0:40
Cost: 0.29¢
Model: google/gemma-4-26b-a4b-it

Map (reference ← swipe → agent)

0:00
cairo_parcels_legacy.geojson is a parcel snapshot stitched together from three legacy provincial systems before unification, and I need to turn it into the foundation for our new central registry. Can you clean it up so we end up with one canonical record per parcel? When duplicates exist, keep the record with the earliest record_seq, and discard any polygon fragments smaller than 1 m². Please write the result to parcels_canonical.geoparquet including these columns: parcel_id (the join key), parcel_class, district, and area_m2. Every feature must be a MultiPolygon, and there should be no null or empty geometries, no invalid geometries, no duplicate geometries, and no artifact slivers.
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System info
{
  "adapter": "openrouter",
  "model": "google/gemma-4-26b-a4b-it",
  "base_url": "https://openrouter.ai/api/v1"
}
0:01
Bash ls -l /work/cairo_parcels_legacy.geojson
-rw-r--r-- 1 agent agent 223991 Jun 16 12:14 /work/cairo_parcels_legacy.geojson
0:03
Write /work/inspect_data.py
content · 14 lines · py
import geopandas as gpd

# Load the data
gdf = gpd.read_file('/work/cairo_parcels_legacy.geojson')

# Inspect columns and first few rows
print("Columns:", gdf.columns.tolist())
print("\nFirst few rows:")
print(gdf.head())
print("\nInfo:")
print(gdf.info())
print("\nGeometry types:")
print(gdf.geometry.type.value_counts())
Wrote /work/inspect_data.py (324 chars).
0:04
Bash python /work/inspect_data.py
Columns: ['parcel_id', 'record_seq', 'parcel_class', 'district', 'area_m2', 'geometry']

First few rows:
   parcel_id  ...                                           geometry
0          1  ...  POLYGON ((640000 815000, 640030 815000, 640030...
1          2  ...  POLYGON ((640050 815000, 640080 815000, 640080...
2          3  ...  POLYGON ((640100 815000, 640130 815000, 640130...
3          4  ...  POLYGON ((640150 815000, 640180 815000, 640180...
4          5  ...  POLYGON ((640200 815000, 640230 815000, 640230...

[5 rows x 6 columns]

Info:
<class 'geopandas.geodataframe.GeoDataFrame'>
RangeIndex: 290 entries, 0 to 289
Data columns (total 6 columns):
 #   Column        Non-Null Count  Dtype   
---  ------        --------------  -----   
 0   parcel_id     290 non-null    int32   
 1   record_seq    290 non-null    int32   
 2   parcel_class  290 non-null    str     
 3   district      290 non-null    str     
 4   area_m2       290 non-null    float64 
 5   geometry      290 non-null    geometry
dtypes: float64(1), geometry(1), int32(2), str(2)
memory usage: 17.8 KB
None

Geometry types:
Polygon         260
MultiPolygon     30
Name: count, dtype: int64
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Write /work/solve.py
content · 75 lines · py
import geopandas as gpd
from shapely.geometry import MultiPolygon, Polygon

def solve():
    # 1. Load the data
    gdf = gpd.read_file('/work/cairo_parcels_legacy.geojson')

    # 2. Clean geometries: remove null/empty and fix invalid geometries
    # Drop null/empty geometries first
    gdf = gdf[gdf.geometry.notnull() & ~gdf.geometry.is_empty].copy()
    
    # Fix invalid geometries (e.g. self-intersections) using buffer(0)
    gdf['geometry'] = gdf['geometry'].buffer(0)
    # Re-filter in case buffer(0) produced empty geometries
    gdf = gdf[gdf.geometry.notnull() & ~gdf.geometry.is_empty].copy()

    # 3. Handle Duplicates: keep record with earliest record_seq per parcel_id
    # Sort by parcel_id and record_seq (ascending)
    gdf = gdf.sort_values(by=['parcel_id', 'record_seq'], ascending=[True, True])
    # Drop duplicates based on parcel_id, keeping the first one (which has lowest record_seq)
    gdf = gdf.drop_duplicates(subset=['parcel_id'], keep='first').copy()

    # 4. Discard polygon fragments smaller than 1 m2
    # Note: The prompt asks to discard fragments smaller than 1m2. 
    # Since we are working with the parsed geometries, we check area of the geometry.
    gdf['area_calc'] = gdf.geometry.area
    gdf = gdf[gdf['area_calc'] >= 1.0].copy()
    # Drop the helper column
    gdf = gdf.drop(columns=['area_calc'])

    # 5. Ensure every feature is a MultiPolygon
    def ensure_multipolygon(geom):
        if isinstance(geom, Polygon):
            return MultiPolygon([geom])
        return geom

    gdf['geometry'] = gdf['geometry'].apply(ensure_multipolygon)

    # 6. Remove duplicate geometries
    # If multiple parcel_ids now have the exact same geometry, we should probably 
    # keep only one. The prompt says "no duplicate geometries".
    # To be safe, we drop duplicate geometries. 
    # Note: In a real registry, different parcels might share a geometry (e.g. zero-area or identical boundaries),
    # but the instruction says "no duplicate geometries".
    gdf = gdf.drop_duplicates(subset=['geometry']).copy()

    # 7. Final cleaning: Ensure no nulls in required columns and columns exist
    # Required columns: parcel_id, parcel_class, district, area_m2
    # area_m2 was in the original, but let's ensure it's accurate based on the geometry
    gdf['area_m2'] = gdf.geometry.area
    
    # Check for nulls in required columns
    cols_to_keep = ['parcel_id', 'parcel_class', 'district', 'area_m2', 'geometry']
    gdf = gdf[cols_to_keep]
    
    # Drop any remaining rows with nulls in these essential columns
    gdf = gdf.dropna(subset=['parcel_id', 'parcel_class', 'district', 'area_m2'])

    # Final verification of geometry types
    # All should be MultiPolygon
    unique_types = gdf.geometry.type.unique()
    print(f"Unique geometry types remaining: {unique_types}")
    
    if any(t != 'MultiPolygon' for t in unique_types):
         # This shouldn't happen given our logic, but as a safeguard:
         gdf['geometry'] = gdf['geometry'].apply(ensure_multipolygon)

    # 8. Write to GeoParquet
    gdf.to_parquet('/work/parcels_canonical.geoparquet')
    print("Successfully wrote parcels_canonical.geoparquet")
    print(f"Final count: {len(gdf)}")

if __name__ == "__main__":
    solve()
Wrote /work/solve.py (3268 chars).
0:18
Bash python /work/solve.py
Unique geometry types remaining: <ArrowStringArray>
['MultiPolygon']
Length: 1, dtype: str
Successfully wrote parcels_canonical.geoparquet
Final count: 210
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Write /work/verify.py
content · 40 lines · py
import geopandas as gpd

def verify():
    gdf = gpd.read_parquet('/work/parcels_canonical.geoparquet')
    
    print("Shape:", gdf.shape)
    print("\nColumns:", gdf.columns.tolist())
    
    # Check geometry type
    geom_types = gdf.geometry.type.unique()
    print("Geometry types:", geom_types)
    
    # Check for null geometries
    print("Null geometries:", gdf.geometry.isnull().any())
    print("Empty geometries:", gdf.geometry.is_empty.any())
    
    # Check for invalid geometries
    print("Invalid geometries:", not gdf.geometry.is_valid.all())
    
    # Check for duplicate geometries
    # We use the WKB representation to compare geometries accurately
    duplicated_geoms = gdf.geometry.duplicated().any()
    print("Duplicate geometries:", duplicated_geoms)
    
    # Check column requirements
    required_cols = ['parcel_id', 'parcel_class', 'district', 'area_m2']
    missing_cols = [c for c in required_cols if c not in gdf.columns]
    print("Missing required columns:", missing_cols)
    
    # Check for nulls in required columns
    nulls_in_cols = gdf[required_cols].isnull().any().any()
    print("Nulls in required columns:", nulls_in_cols)
    
    # Check area requirement (> 1)
    small_areas = (gdf.geometry.area < 1.0).any()
    print("Areas < 1m2:", small_areas)

if __name__ == "__main__":
    verify()
Wrote /work/verify.py (1348 chars).
0:26
Bash python /work/verify.py
Shape: (210, 5)

Columns: ['parcel_id', 'parcel_class', 'district', 'area_m2', 'geometry']
Geometry types: <ArrowStringArray>
['MultiPolygon']
Length: 1, dtype: str
Null geometries: False
Empty geometries: False
Invalid geometries: False
Duplicate geometries: False
Missing required columns: []
Nulls in required columns: False
Areas < 1m2: False
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