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Preserve column names in empty Dataframe #61143

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Preserve column names in empty Dataframe #61143

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2 changes: 1 addition & 1 deletion pandas/core/frame.py
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Original file line number Diff line number Diff line change
Expand Up @@ -2231,7 +2231,7 @@ def maybe_reorder(

if is_iterator(data):
if nrows == 0:
return cls()
return cls(columns=columns)

try:
first_row = next(data)
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7 changes: 7 additions & 0 deletions pandas/core/frame_test_constructors.py
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Original file line number Diff line number Diff line change
@@ -0,0 +1,7 @@
import pandas as pd
def test_empty_df_preserve_col():
rows = []
df = pd.DataFrame.from_records(iter(rows), columns=['col_1', 'Col_2'], nrows=0)
assert list(df.columns)==['col_1', 'Col_2']
assert len(df) == 0
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Can you follow the dev docs here: https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#writing-tests

Namely, search the current tests for from_records and that should give a good indication of where to place this test.


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