add table utils

csst_common/utils/__init__.py

@@ -12,6 +12,4 @@ Modified-History:
 from ._module_docstr import ModuleHeader
 from ._retry import retry
 from .tempfile import randfile
-
-
-
+from .table_utils import table_to_hdu, hdu_to_table

csst_common/utils/table_utils.py

+"""
+Identifier:     csst_dadel/csst_dadel/utils.py
+Name:           utils.py
+Description:    Table utils.
+Author:         Bo Zhang
+Created:        2024-02-18
+Modified-History:
+    2024-02-18, Bo Zhang, implement utils for conversion between Table and BinTableHDU
+"""
+from astropy import table
+from astropy.io import fits
+
+
+def table_to_hdu(tbl: table.Table, name: str = "") -> fits.BinTableHDU:
+    """Convert a table to a BinTableHDU."""
+    # encode meta
+    encoded_tbl = fits.connect._encode_mixins(tbl)
+    # convert to HDU
+    hdu = fits.table_to_hdu(encoded_tbl)
+    # add HDU name
+    hdu.name = name
+    return hdu
+
+
+def hdu_to_table(hdu: fits.BinTableHDU) -> table.Table:
+    """Convert a BinTableHDU to a table."""
+    return table.Table.read(hdu)