dc-l2-cairo-invalid-dedup

Status: done
Score: 0.914
Duration: 1:28
Cost: 0.22¢
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.
0:00
System info
{
  "adapter": "openrouter",
  "model": "google/gemma-4-26b-a4b-it",
  "base_url": "https://openrouter.ai/api/v1"
}
0:02
Bash ls -F
ls -F
cairo_parcels_legacy.geojson
0:07
Write /work/inspect_data.py
content · 14 lines · py
import geopandas as gpd

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

print("Initial info:")
print(gdf.info())
print("\nFirst few rows:")
print(gdf.head())
print("\nGeometry type counts:")
print(gdf.geom_type.value_counts())
print("\nColumns:")
print(gdf.columns)
Wrote /work/inspect_data.py (288 chars).
0:09
Bash python /work/inspect_data.py
python /work/inspect_data.py
Initial 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

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]

Geometry type counts:
Polygon         260
MultiPolygon     30
Name: count, dtype: int64

Columns:
Index(['parcel_id', 'record_seq', 'parcel_class', 'district', 'area_m2',
       'geometry'],
      dtype='str')
0:34
Write /work/solve.py
content · 76 lines · py
import geopandas as gpd
from shapely.geometry import MultiPolygon, Polygon

def clean_parcels(input_file, output_file):
    # 1. Load the data
    gdf = gpd.read_file(input_file)
    
    # 2. Handle invalid geometries
    # Ensure geometries are valid. If not, try to fix them using buffer(0)
    gdf['geometry'] = gdf['geometry'].buffer(0)
    
    # 3. Remove null or empty geometries
    gdf = gdf[gdf.geometry.notnull() & ~gdf.geometry.is_empty]
    
    # 4. Handle duplicates based on parcel_id
    # Keep the record with the earliest record_seq
    gdf = gdf.sort_values('record_seq').drop_duplicates(subset='parcel_id', keep='first')
    
    # 5. Discard polygon fragments smaller than 1 m^2
    # Note: The requirement says "discard any polygon fragments smaller than 1 m^2".
    # Usually this implies that if a parcel is represented by multiple parts, 
    # we should filter the parts. However, the instructions also say "Every feature must be a MultiPolygon".
    # This suggests we should process the geometry components.
    
    def filter_small_parts(geom):
        if geom.is_empty:
            return geom
        
        # If it's a Polygon, check its area
        if isinstance(geom, Polygon):
            return geom if geom.area >= 1.0 else None
        
        # If it's a MultiPolygon, check each part
        if isinstance(geom, MultiPolygon):
            parts = [p for p in geom.geoms if p.area >= 1.0]
            if not parts:
                return None
            return MultiPolygon(parts)
        
        return geom

    # Apply filtering to geometries
    gdf['geometry'] = gdf['geometry'].apply(filter_small_parts)
    
    # Drop any rows that became empty/None after filtering parts
    gdf = gdf[gdf.geometry.notnull() & ~gdf.geometry.is_empty]
    
    # 6. 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)

    # 7. Remove duplicate geometries
    gdf = gdf.drop_duplicates(subset='geometry')

    # 8. Final column selection and cleanup
    # Required columns: parcel_id, parcel_class, district, area_m2
    # We'll also recalculate area_m2 based on the cleaned geometry to be sure, 
    # or just keep the column if it's expected to be the one from the record.
    # The prompt says "including these columns", implying they should be present.
    # Let's recalculate area_m2 to ensure it matches the cleaned geometry.
    gdf['area_m2'] = gdf['geometry'].area
    
    output_cols = ['parcel_id', 'parcel_class', 'district', 'area_m2', 'geometry']
    gdf = gdf[output_cols]

    # Save to geoparquet
    gdf.to_parquet(output_file)
    print(f"Successfully processed {len(gdf)} parcels.")

if __name__ == "__main__":
    clean_parcels('cairo_parcels_legacy.geojson', 'parcels_canonical.geoparquet')
Wrote /work/solve.py (2939 chars).
0:35
Bash python /work/solve.py
python /work/solve.py
Successfully processed 210 parcels.
1:07
Write /work/validate_result.py
content · 37 lines · py
import geopandas as gpd

# Load the result
gdf = gpd.read_parquet('parcels_canonical.geoparquet')

print("Final info:")
print(gdf.info())
print("\nGeometry type counts:")
print(gdf.geom_type.value_counts())

# Check for duplicates in parcel_id
duplicates = gdf.duplicated(subset='parcel_id').sum()
print(f"\nDuplicate parcel_ids: {duplicates}")

# Check for null/empty geometries
null_empty = gdf.geometry.isna().sum() + gdf.geometry.is_empty.sum()
print(f"Null or empty geometries: {null_empty}")

# Check for invalid geometries
invalid = gdf.geometry.is_valid.sum()
print(f"Invalid geometries: {len(gdf) - invalid}")

# Check for duplicate geometries
geom_duplicates = gdf.duplicated(subset='geometry').sum()
print(f"Duplicate geometries: {geom_duplicates}")

# Check all are MultiPolygon
all_multipolygon = all(gdf.geom_type == 'MultiPolygon')
print(f"All are MultiPolygon: {all_multipolygon}")

# Check area_m2 matches geometry area
area_mismatch = (gdf['area_m2'] - gdf.geometry.area).abs().max()
print(f"Max area mismatch: {area_mismatch}")

# Check smallest area
print(f"Minimum area: {gdf['area_m2'].min()}")
Wrote /work/validate_result.py (1117 chars).
1:09
Bash python /work/validate_result.py
python /work/validate_result.py
Final info:
<class 'geopandas.geodataframe.GeoDataFrame'>
RangeIndex: 210 entries, 0 to 209
Data columns (total 5 columns):
 #   Column        Non-Null Count  Dtype   
---  ------        --------------  -----   
 0   parcel_id     210 non-null    int32   
 1   parcel_class  210 non-null    str     
 2   district      210 non-null    str     
 3   area_m2       210 non-null    float64 
 4   geometry      210 non-null    geometry
dtypes: float64(1), geometry(1), int32(1), str(2)
memory usage: 12.2 KB
None

Geometry type counts:
MultiPolygon    210
Name: count, dtype: int64

Duplicate parcel_ids: 0
Null or empty geometries: 0
Invalid geometries: 0
Duplicate geometries: 0
All are MultiPolygon: True
Max area mismatch: 0.0
Minimum area: 300.0
1:26