diff --git a/src/ngio/tables/v1/_roi_table.py b/src/ngio/tables/v1/_roi_table.py index 0a0522bf..b645f53f 100644 --- a/src/ngio/tables/v1/_roi_table.py +++ b/src/ngio/tables/v1/_roi_table.py @@ -86,10 +86,10 @@ def _dataframe_to_rois( ) -> dict[str, Roi]: """Convert a DataFrame to a WorldCooROI object.""" # Validate the columns of the DataFrame - _required_columns = set(dataframe.columns).intersection(set(required_columns)) - if len(_required_columns) != len(required_columns): + _missing_columns = set(required_columns).difference(set(dataframe.columns)) + if len(_missing_columns) != 0: raise NgioTableValidationError( - f"Could not find required columns: {_required_columns} in the table." + f"Could not find required columns: {_missing_columns} in the table." ) extra_columns = set(dataframe.columns).difference(