dd-l2-bangkok-multicrs-audit

Status: done
Score: 100
Duration: 1:50
Cost: 0.42¢
Model: google/gemma-4-26b-a4b-it

Map (reference ← swipe → agent)

0:00
A contractor just shipped `bangkok_contractor_delivery.gpkg` and I need a defect cite-sheet before I sign off. Please walk every layer in the file and write one row per layer to `crs_audit.csv` with these columns: layer_name, declared_crs (formatted as `EPSG:NNNN`), geometry_type, feature_count, sample_x and sample_y for a sample coordinate taken from the layer as it sits on disk, and encoding_detected. For encoding_detected, look at the text attributes for anomalies and report either `latin1-mojibake` or `utf-8`.
0:00
System info
{
  "adapter": "openrouter",
  "model": "google/gemma-4-26b-a4b-it",
  "base_url": "https://openrouter.ai/api/v1"
}
0:01
Bash ls -l bangkok_contractor_delivery.gpkg
-rw-r--r-- 1 agent agent 2703360 Jun 19 02:42 bangkok_contractor_delivery.gpkg
0:28
Write /work/solve.py
content · 86 lines · py
import geopandas as gpd
import fiona
import pandas as pd
import csv

def check_encoding(df):
    """
    Checks if the text columns in a dataframe contain mojibake.
    A simple way is to try to encode/decode or look for specific patterns.
    Here we will check if any string column contains characters that look like mojibake.
    Specifically, we'll check if strings can be converted from latin-1 to utf-8 without error 
    but look 'weird', or more simply, if we can detect common mojibake patterns.
    Actually, a more robust way is to check if strings contain common replacement characters 
    or if they were likely read as latin-1 when they were utf-8.
    """
    # For the sake of this task, let's see if we can identify latin1-mojibake.
    # A common sign of latin1-mojibake is seeing things like 'é' instead of 'é'.
    
    # We'll check all object (string) columns
    for col in df.select_dtypes(include=['object']).columns:
        for val in df[col].dropna().unique():
            if isinstance(val, str):
                # Check for patterns like à followed by a character, which is common in utf-8 read as latin-1
                # or just try to see if it's "broken"
                try:
                    # If it's valid utf-8 and contains high-bit characters that look like mojibake
                    # This is a heuristic.
                    if any(ord(c) > 127 for c in val):
                        # Try to see if decoding it as latin-1 and re-encoding to utf-8 "fixes" it
                        # Or if it's already looking like mojibake.
                        # Let's look for the à pattern specifically.
                        if 'Ã' in val:
                            return 'latin1-mojibake'
                except:
                    pass
    return 'utf-8'

def audit_gpkg(file_path, output_csv):
    layers = fiona.listlayers(file_path)
    audit_results = []

    for layer in layers:
        gdf = gpd.read_file(file_path, layer=layer)
        
        # CRS
        if gdf.crs is not None:
            declared_crs = f"EPSG:{gdf.crs.to_epsg()}" if gdf.crs.to_epsg() else str(gdf.crs)
        else:
            declared_crs = "None"
            
        # Geometry Type
        if not gdf.empty:
            geom_type = gdf.geometry.type.iloc[0]
            # Sample coords
            sample_row = gdf.iloc[0]
            sample_geom = sample_row.geometry
            if sample_geom.is_empty:
                sample_x, sample_y = None, None
            else:
                sample_x, sample_y = sample_geom.centroid.x, sample_geom.centroid.y
        else:
            geom_type = "Unknown"
            sample_x, sample_y = None, None

        feature_count = len(gdf)
        
        # Encoding detection
        encoding = check_encoding(gdf)
        
        audit_results.append({
            'layer_name': layer,
            'declared_crs': declared_crs,
            'geometry_type': geom_type,
            'feature_count': feature_count,
            'sample_x': sample_x,
            'sample_y': sample_y,
            'encoding_detected': encoding
        })

    df_audit = pd.DataFrame(audit_results)
    df_audit.to_csv(output_csv, index=False)
    print(f"Audit complete. Results written to {output_csv}")

if __name__ == "__main__":
    audit_gpkg('bangkok_contractor_delivery.gpkg', 'crs_audit.csv')
Wrote /work/solve.py (3366 chars).
0:30
Bash python solve.py
Audit complete. Results written to crs_audit.csv
/work/solve.py:20: Pandas4Warning: For backward compatibility, 'str' dtypes are included by select_dtypes when 'object' dtype is specified. This behavior is deprecated and will be removed in a future version. Explicitly pass 'str' to `include` to select them, or to `exclude` to remove them and silence this warning.
See https://pandas.pydata.org/docs/user_guide/migration-3-strings.html#string-migration-select-dtypes for details on how to write code that works with pandas 2 and 3.
  for col in df.select_dtypes(include=['object']).columns:
/work/solve.py:20: Pandas4Warning: For backward compatibility, 'str' dtypes are included by select_dtypes when 'object' dtype is specified. This behavior is deprecated and will be removed in a future version. Explicitly pass 'str' to `include` to select them, or to `exclude` to remove them and silence this warning.
See https://pandas.pydata.org/docs/user_guide/migration-3-strings.html#string-migration-select-dtypes for details on how to write code that works with pandas 2 and 3.
  for col in df.select_dtypes(include=['object']).columns:
/work/solve.py:20: Pandas4Warning: For backward compatibility, 'str' dtypes are included by select_dtypes when 'object' dtype is specified. This behavior is deprecated and will be removed in a future version. Explicitly pass 'str' to `include` to select them, or to `exclude` to remove them and silence this warning.
See https://pandas.pydata.org/docs/user_guide/migration-3-strings.html#string-migration-select-dtypes for details on how to write code that works with pandas 2 and 3.
  for col in df.select_dtypes(include=['object']).columns:
0:32
Bash cat crs_audit.csv
layer_name,declared_crs,geometry_type,feature_count,sample_x,sample_y,encoding_detected
parcels,EPSG:24047,Polygon,4000,657706.4571303247,1509274.702150785,utf-8
roads,EPSG:32647,LineString,5000,656996.3371533038,1509487.963830215,utf-8
markets,EPSG:4326,Point,1000,100.4533,13.655000000000001,utf-8
0:56
Write /work/solve.py
content · 69 lines · py
import geopandas as gpd
import fiona
import pandas as pd

def check_encoding(df):
    """
    Checks if the text columns in a dataframe contain mojibake.
    We'll look for common patterns like 'Ã' which often appears when UTF-8 is read as Latin-1.
    """
    for col in df.select_dtypes(include=['object']).columns:
        for val in df[col].dropna().unique():
            if isinstance(val, str):
                # Heuristic: check for the common 'Ã' pattern or other typical mojibake indicators
                # Specifically, the presence of multiple high-bit chars that look like broken UTF-8
                if 'Ã' in val:
                    return 'latin1-mojibake'
    return 'utf-8'

def audit_gpkg(file_path, output_csv):
    layers = fiona.listlayers(file_path)
    audit_results = []

    for layer in layers:
        gdf = gpd.read_file(file_path, layer=layer)
        
        # CRS
        if gdf.crs is not None:
            epsg = gdf.crs.to_epsg()
            declared_crs = f"EPSG:{epsg}" if epsg else str(gdf.crs)
        else:
            declared_crs = "None"
            
        # Geometry Type
        if not gdf.empty:
            geom_type = gdf.geometry.type.iloc[0]
            # Sample coords: Take the centroid of the first geometry
            sample_row = gdf.iloc[0]
            sample_geom = sample_row.geometry
            if sample_geom.is_empty:
                sample_x, sample_y = None, None
            else:
                # Using centroid to get a representative point for the sample
                sample_x, sample_y = sample_geom.centroid.x, sample_geom.centroid.y
        else:
            geom_type = "Unknown"
            sample_x, sample_y = None, None

        feature_count = len(gdf)
        
        # Encoding detection
        encoding = check_encoding(gdf)
        
        audit_results.append({
            'layer_name': layer,
            'declared_crs': declared_crs,
            'geometry_type': geom_type,
            'feature_count': feature_count,
            'sample_x': sample_x,
            'sample_y': sample_y,
            'encoding_detected': encoding
        })

    df_audit = pd.DataFrame(audit_results)
    df_audit.to_csv(output_csv, index=False)
    print(f"Audit complete. Results written to {output_csv}")

if __name__ == "__main__":
    audit_gpkg('bangkok_contractor_delivery.gpkg', 'crs_audit.csv')
Wrote /work/solve.py (2385 chars).
1:06
Bash # First, let's check if there's actually any mojibake in the file by looking at ...
# First, let's check if there's actually any mojibake in the file by looking at the content manually if possible.
# Since I can't "look" at the content easily without a script, I'll write a script to check all layers more aggressively.

cat << 'EOF' > /work/check_mojibake.py
import geopandas as gpd
import fiona

def check_mojibake_aggressive(gdf):
    for col in gdf.select_dtypes(include=['object']).columns:
        for val in gdf[col].dropna().unique():
            if isinstance(val, str):
                # Looking for common mojibake patterns. 
                # A very common one is 'Ã' followed by another char
                # such as é for é.
                import re
                if re.search(r'Ã[^\s]', val):
                    return True
    return False

layers = fiona.listlayers('bangkok_contractor_delivery.gpkg')
for layer in layers:
    gdf = gpd.read_file('bangkok_contractor_delivery.gpkg', layer=layer)
    if check_mojibake_aggressive(gdf):
        print(f"Found mojibake in layer: {layer}")
    else:
        print(f"No mojibake found in layer: {layer}")

EOF

python /work/check_mojibake.py
No mojibake found in layer: parcels
No mojibake found in layer: roads
No mojibake found in layer: markets
/work/check_mojibake.py:5: Pandas4Warning: For backward compatibility, 'str' dtypes are included by select_dtypes when 'object' dtype is specified. This behavior is deprecated and will be removed in a future version. Explicitly pass 'str' to `include` to select them, or to `exclude` to remove them and silence this warning.
See https://pandas.pydata.org/docs/user_guide/migration-3-strings.html#string-migration-select-dtypes for details on how to write code that works with pandas 2 and 3.
  for col in gdf.select_dtypes(include=['object']).columns:
/work/check_mojibake.py:5: Pandas4Warning: For backward compatibility, 'str' dtypes are included by select_dtypes when 'object' dtype is specified. This behavior is deprecated and will be removed in a future version. Explicitly pass 'str' to `include` to select them, or to `exclude` to remove them and silence this warning.
See https://pandas.pydata.org/docs/user_guide/migration-3-strings.html#string-migration-select-dtypes for details on how to write code that works with pandas 2 and 3.
  for col in gdf.select_dtypes(include=['object']).columns:
/work/check_mojibake.py:5: Pandas4Warning: For backward compatibility, 'str' dtypes are included by select_dtypes when 'object' dtype is specified. This behavior is deprecated and will be removed in a future version. Explicitly pass 'str' to `include` to select them, or to `exclude` to remove them and silence this warning.
See https://pandas.pydata.org/docs/user_guide/migration-3-strings.html#string-migration-select-dtypes for details on how to write code that works with pandas 2 and 3.
  for col in gdf.select_dtypes(include=['object']).columns:
1:21
Bash # Let's check the data for "roads" or "parcels" for any non-ASCII.
# Let's check the data for "roads" or "parcels" for any non-ASCII.
# Maybe there is something else.

cat << 'EOF' > /work/inspect_data.py
import geopandas as gpd

layers = ['parcels', 'roads', 'markets']
for layer in layers:
    gdf = gpd.read_file('bangkok_contractor_delivery.gpkg', layer=layer)
    print(f"Layer: {layer}")
    for col in gdf.select_dtypes(include=['object']).columns:
        print(f"  Column: {col}")
        for val in gdf[col].dropna().unique()[:5]:
            print(f"    {val}")
            # Check for characters > 127
            if any(ord(c) > 127 for c in str(val)):
                 print("      !!! Non-ASCII detected !!!")
EOF

python /work/inspect_data.py
Layer: parcels
  Column: id
    P00000
    P00001
    P00002
    P00003
    P00004
  Column: name_th
    แปลงที่ดิน บางรัก
      !!! Non-ASCII detected !!!
    แปลงที่ดิน ปทุมวัน
      !!! Non-ASCII detected !!!
    แปลงที่ดิน วัฒนา
      !!! Non-ASCII detected !!!
    แปลงที่ดิน คลองเตย
      !!! Non-ASCII detected !!!
    แปลงที่ดิน ดินแดง
      !!! Non-ASCII detected !!!
  Column: owner_class
    private
    state
    religious
Layer: roads
  Column: id
    R00000
    R00001
    R00002
    R00003
    R00004
  Column: name
    ถนนสุขุมวิท
      !!! Non-ASCII detected !!!
    ถนนพระราม 4
      !!! Non-ASCII detected !!!
    ถนนพระราม 9
      !!! Non-ASCII detected !!!
    ถนนรัชดาภิเษก
      !!! Non-ASCII detected !!!
    ถนนเพชรบุรี
      !!! Non-ASCII detected !!!
  Column: highway
    primary
    secondary
    tertiary
    residential
    service
Layer: markets
  Column: id
    M00000
    M00001
    M00002
    M00003
    M00004
  Column: name_th
    ตลาดนัดจตุจักร
      !!! Non-ASCII detected !!!
    ตลาดอ.ต.ก.
      !!! Non-ASCII detected !!!
    ตลาดคลองเตย
      !!! Non-ASCII detected !!!
    ตลาดสะพานขาว
      !!! Non-ASCII detected !!!
    ตลาดบางรัก
      !!! Non-ASCII detected !!!
  Column: kind
    fresh
    wet
    night
/work/inspect_data.py:7: Pandas4Warning: For backward compatibility, 'str' dtypes are included by select_dtypes when 'object' dtype is specified. This behavior is deprecated and will be removed in a future version. Explicitly pass 'str' to `include` to select them, or to `exclude` to remove them and silence this warning.
See https://pandas.pydata.org/docs/user_guide/migration-3-strings.html#string-migration-select-dtypes for details on how to write code that works with pandas 2 and 3.
  for col in gdf.select_dtypes(include=['object']).columns:
/work/inspect_data.py:7: Pandas4Warning: For backward compatibility, 'str' dtypes are included by select_dtypes when 'object' dtype is specified. This behavior is deprecated and will be removed in a future version. Explicitly pass 'str' to `include` to select them, or to `exclude` to remove them and silence this warning.
See https://pandas.pydata.org/docs/user_guide/migration-3-strings.html#string-migration-select-dtypes for details on how to write code that works with pandas 2 and 3.
  for col in gdf.select_dtypes(include=['object']).columns:
/work/inspect_data.py:7: Pandas4Warning: For backward compatibility, 'str' dtypes are included by select_dtypes when 'object' dtype is specified. This behavior is deprecated and will be removed in a future version. Explicitly pass 'str' to `include` to select them, or to `exclude` to remove them and silence this warning.
See https://pandas.pydata.org/docs/user_guide/migration-3-strings.html#string-migration-select-dtypes for details on how to write code that works with pandas 2 and 3.
  for col in gdf.select_dtypes(include=['object']).columns:
1:37
Write /work/solve.py
content · 72 lines · py
import geopandas as gpd
import fiona
import pandas as pd
import re

def check_encoding(df):
    """
    Checks if the text columns in a dataframe contain mojibake.
    In the parcels and roads layers, we saw characters like 'แปลงที่ดิน'.
    This is a classic sign of UTF-8 bytes being interpreted as Latin-1.
    """
    for col in df.select_dtypes(include=['object']).columns:
        for val in df[col].dropna().unique():
            if isinstance(val, str):
                # Check for common mojibake patterns. 
                # Patterns like 'à' followed by other accented characters 
                # are very common when UTF-8 is read as Latin-1.
                # We'll check for the specific pattern seen in the inspection.
                if re.search(r'à[^\x00-\x7F]', val):
                    return 'latin1-mojibake'
    return 'utf-8'

def audit_gpkg(file_path, output_csv):
    layers = fiona.listlayers(file_path)
    audit_results = []

    for layer in layers:
        gdf = gpd.read_file(file_path, layer=layer)
        
        # CRS
        if gdf.crs is not None:
            epsg = gdf.crs.to_epsg()
            declared_crs = f"EPSG:{epsg}" if epsg else str(gdf.crs)
        else:
            declared_crs = "None"
            
        # Geometry Type
        if not gdf.empty:
            geom_type = gdf.geometry.type.iloc[0]
            # Sample coords: Take the centroid of the first geometry
            sample_row = gdf.iloc[0]
            sample_geom = sample_row.geometry
            if sample_geom.is_empty:
                sample_x, sample_y = None, None
            else:
                sample_x, sample_y = sample_geom.centroid.x, sample_geom.centroid.y
        else:
            geom_type = "Unknown"
            sample_x, sample_y = None, None

        feature_count = len(gdf)
        
        # Encoding detection
        encoding = check_encoding(gdf)
        
        audit_results.append({
            'layer_name': layer,
            'declared_crs': declared_crs,
            'geometry_type': geom_type,
            'feature_count': feature_count,
            'sample_x': sample_x,
            'sample_y': sample_y,
            'encoding_detected': encoding
        })

    df_audit = pd.DataFrame(audit_results)
    df_audit.to_csv(output_csv, index=False)
    print(f"Audit complete. Results written to {output_csv}")

if __name__ == "__main__":
    audit_gpkg('bangkok_contractor_delivery.gpkg', 'crs_audit.csv')
Wrote /work/solve.py (2485 chars).
1:38
Bash python solve.py
Audit complete. Results written to crs_audit.csv
/work/solve.py:12: Pandas4Warning: For backward compatibility, 'str' dtypes are included by select_dtypes when 'object' dtype is specified. This behavior is deprecated and will be removed in a future version. Explicitly pass 'str' to `include` to select them, or to `exclude` to remove them and silence this warning.
See https://pandas.pydata.org/docs/user_guide/migration-3-strings.html#string-migration-select-dtypes for details on how to write code that works with pandas 2 and 3.
  for col in df.select_dtypes(include=['object']).columns:
/work/solve.py:12: Pandas4Warning: For backward compatibility, 'str' dtypes are included by select_dtypes when 'object' dtype is specified. This behavior is deprecated and will be removed in a future version. Explicitly pass 'str' to `include` to select them, or to `exclude` to remove them and silence this warning.
See https://pandas.pydata.org/docs/user_guide/migration-3-strings.html#string-migration-select-dtypes for details on how to write code that works with pandas 2 and 3.
  for col in df.select_dtypes(include=['object']).columns:
/work/solve.py:12: Pandas4Warning: For backward compatibility, 'str' dtypes are included by select_dtypes when 'object' dtype is specified. This behavior is deprecated and will be removed in a future version. Explicitly pass 'str' to `include` to select them, or to `exclude` to remove them and silence this warning.
See https://pandas.pydata.org/docs/user_guide/migration-3-strings.html#string-migration-select-dtypes for details on how to write code that works with pandas 2 and 3.
  for col in df.select_dtypes(include=['object']).columns:
1:41
Bash cat crs_audit.csv
layer_name,declared_crs,geometry_type,feature_count,sample_x,sample_y,encoding_detected
parcels,EPSG:24047,Polygon,4000,657706.4571303247,1509274.702150785,latin1-mojibake
roads,EPSG:32647,LineString,5000,656996.3371533038,1509487.963830215,latin1-mojibake
markets,EPSG:4326,Point,1000,100.4533,13.655000000000001,utf-8
1:50