Merge pull request #76 from astronomy-commons/sean/fix-from-dataframe…

…-index

Fix index not being set correctly in `from_dataframe`

src/lsdb/loaders/dataframe/dataframe_catalog_loader.py

@@ -162,7 +162,7 @@ def _generate_dask_df_and_map(
             pixel_dfs.append(df)
 
         # Generate Dask Dataframe with original schema
-        schema = pd.DataFrame(columns=pixel_dfs[0].columns).astype(pixel_dfs[0].dtypes)
+        schema = pixel_dfs[0].iloc[:0, :].copy()
         ddf, total_rows = self._generate_dask_dataframe(pixel_dfs, schema)
 
         return ddf, ddf_pixel_map, total_rows

tests/lsdb/loaders/dataframe/test_from_dataframe.py

@@ -2,6 +2,7 @@
 import pandas as pd
 import pytest
 from hipscat.catalog import CatalogType
+from hipscat.pixel_math.hipscat_id import HIPSCAT_ID_COLUMN
 from hipscat.pixel_tree.pixel_node_type import PixelNodeType
 
 import lsdb
@@ -31,6 +32,8 @@ def test_from_dataframe(small_sky_order1_df, small_sky_order1_catalog):
     assert isinstance(catalog, lsdb.Catalog)
     # Catalogs have the same information
     assert catalog.hc_structure.catalog_info == small_sky_order1_catalog.hc_structure.catalog_info
+    # Index is set to hipscat index
+    assert catalog._ddf.index.name == HIPSCAT_ID_COLUMN
     # Dataframes have the same data (column data types may differ)
     pd.testing.assert_frame_equal(
         catalog.compute().sort_index(),