From da9525fedea764d7939475988632bd4ef74a3aca Mon Sep 17 00:00:00 2001
From: domfournier <dominiquef@mirageoscience.com>
Date: Wed, 11 Mar 2026 09:07:19 -0700
Subject: [PATCH] Store and re-use datetime

---
 simpeg/directives/_directives.py | 12 +++++++++---
 simpeg/directives/_save_geoh5.py | 21 ++++++++++++++++++---
 2 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/simpeg/directives/_directives.py b/simpeg/directives/_directives.py
index 00340066e1..e70bb9a1a2 100644
--- a/simpeg/directives/_directives.py
+++ b/simpeg/directives/_directives.py
@@ -2676,8 +2676,14 @@ class ScaleMisfitMultipliers(InversionDirective):
     Parameters
     ----------
 
-    path : str
+    filepath : str
         Path to save the chi-factors log file.
+    nesting : list of lists
+        Nested list structure that matches the structure of the misfit functions in the inverse problem.
+    target_chi : float
+        Target chi-factor for the misfit functions. Misfit functions with chi-factors below this value will be scaled more aggressively.
+    headers : list of str
+        List of headers for the chi-factors log file.
     """
 
     def __init__(
@@ -2695,9 +2701,9 @@ def __init__(
         self.headers = headers
 
         if path is None:
-            path = pathlib.Path("./")
+            path = pathlib.Path("./ChiFactors.log")
 
-        self.filepath = path / "ChiFactors.log"
+        self.filepath = path
 
         super().__init__(**kwargs)
 
diff --git a/simpeg/directives/_save_geoh5.py b/simpeg/directives/_save_geoh5.py
index a06a48c77b..8647c96993 100644
--- a/simpeg/directives/_save_geoh5.py
+++ b/simpeg/directives/_save_geoh5.py
@@ -384,16 +384,27 @@ def joint_index(self, value: list[int] | None):
 
 
 class SaveLogFilesGeoH5(BaseSaveGeoH5):
+    def __init__(
+        self,
+        h5_object,
+        start_date_time: str,
+        **kwargs,
+    ):
+
+        self.time_stamp = start_date_time
+        super().__init__(h5_object, **kwargs)
 
     def write(self, iteration: int, **_):
         dirpath = Path(self._workspace.h5file).parent
-        filepath = dirpath / "SimPEG.out"
+        filepath = dirpath / f"SimPEG_{self.time_stamp}.out"
 
         if iteration == 0:
             with open(filepath, "w", encoding="utf-8") as f:
                 f.write("iteration beta phi_d phi_m time\n")
         log = []
-        with open(dirpath / "SimPEG.log", "r", encoding="utf-8") as file:
+        with open(
+            dirpath / f"SimPEG_{self.time_stamp}.log", "r", encoding="utf-8"
+        ) as file:
             iteration = 0
             for line in file:
                 val = re.findall(r"[+-]?(?:0|[1-9]\d*)(?:\.\d*)?(?:[eE][+-]?\d+)", line)
@@ -420,7 +431,11 @@ def save_log(self):
         with fetch_active_workspace(self._workspace, mode="r+") as w_s:
             h5_object = w_s.get_entity(self.h5_object)[0]
 
-            for file in ["SimPEG.out", "SimPEG.log", "ChiFactors.log"]:
+            for file in [
+                f"SimPEG_{self.time_stamp}.out",
+                f"SimPEG_{self.time_stamp}.log",
+                f"ChiFactors_{self.time_stamp}.log",
+            ]:
                 filepath = dirpath / file
 
                 if not filepath.is_file():