Revert "Convert N/A values to NoneType objects."

This reverts commit 6870c08d484f482cc2f2501d28b474636dd0810d.

The "read_csv_file" should return the data in the CSV file, as is,
before processing the N/A values.

1 files changed, 5 insertions, 12 deletions

diff --git a/r_qtl/r_qtl2.py b/r_qtl/r_qtl2.py
index ec70c5c..b1eae90 100644
--- a/r_qtl/r_qtl2.py
+++ b/r_qtl/r_qtl2.py
@@ -6,7 +6,7 @@ import json
 from pathlib import Path
 from functools import reduce, partial
 from zipfile import ZipFile, is_zipfile
-from typing import Union, Iterator, Iterable, Callable, Optional, Sequence
+from typing import Union, Iterator, Iterable, Callable, Optional
 
 import yaml
 
@@ -572,21 +572,14 @@ def read_text_file(filepath: Union[str, Path]) -> Iterator[str]:
             yield line
 
 
-def read_csv_file(
-        filepath: Union[str, Path],
-        separator: str = ",",
-        comment_char: str = "#",
-        na_strings: Sequence[str] = ["NA"]
-) -> Iterator[tuple[str, ...]]:
+def read_csv_file(filepath: Union[str, Path],
+                  separator: str = ",",
+                  comment_char: str = "#") -> Iterator[tuple[str, ...]]:
     """Read a file as a csv file."""
-    def __none_if_na__(val):
-        return None if val in na_strings else val
-
     for line in read_text_file(filepath):
         if line.startswith(comment_char):
             continue
-        yield tuple(__none_if_na__(field.strip())
-                    for field in line.split(separator))
+        yield tuple(field.strip() for field in line.split(separator))
 
 
 def read_csv_file_headers(