Add note in documentation.

1 files changed, 1 insertions, 1 deletions

diff --git a/r_qtl/r_qtl2.py b/r_qtl/r_qtl2.py
index b1eae90..06175ce 100644
--- a/r_qtl/r_qtl2.py
+++ b/r_qtl/r_qtl2.py
@@ -575,7 +575,7 @@ def read_text_file(filepath: Union[str, Path]) -> Iterator[str]:
 def read_csv_file(filepath: Union[str, Path],
                   separator: str = ",",
                   comment_char: str = "#") -> Iterator[tuple[str, ...]]:
-    """Read a file as a csv file."""
+    """Read a file as a csv file. This does not process the N/A values."""
     for line in read_text_file(filepath):
         if line.startswith(comment_char):
             continue