Reverting PR #3179 which breaks csv logging.

The header and previous rows are appended for every save call. This in unintended behavior. - changing back to 'write' mode instead of 'append' mode
C-Achard · Feb 13, 2026 · Jan 13, 2026 · Jan 16, 2026 · Jan 16, 2026 · Jan 16, 2026
commit ce2e26040b9c977e6aeded207f3610cab1ed393c
diff --git a/deeplabcut/pose_estimation_pytorch/runners/logger.py b/deeplabcut/pose_estimation_pytorch/runners/logger.py
@@ -438,7 +438,7 @@ def log(self, metrics: dict[str, Any], step: Optional[int] = None) -> None:
     def save(self):
         """Saves the metrics to the file system"""
         logs = self._prepare_logs()
-        with open(self.log_file, "a", newline="") as f:
+        with open(self.log_file, "w", newline="") as f:
             writer = csv.writer(f)
             writer.writerows(logs)