CoDICE l2 geometric factor: update mode calculation

imap_processing/codice/codice_l2.py

@@ -9,6 +9,7 @@
 dataset = process_codice_l2(l1_filename)
 """
 
+import datetime
 import logging
 from pathlib import Path
 
@@ -41,6 +42,7 @@
     SW_POSITIONS,
 )
 from imap_processing.codice.utils import apply_replacements_to_attrs
+from imap_processing.spice.time import et_to_datetime64, ttj2000ns_to_et
 
 logger = logging.getLogger(__name__)
 
@@ -315,7 +317,19 @@ def compute_geometric_factors(
     # Perform the comparison and calculate modes
     # Modes will be true (reduced mode) anywhere half_spin > rgfo_half_spin otherwise
     # false (full mode)
-    modes = half_spin_per_esa_step > rgfo_half_spin
+    # TODO: The mode calculation will need to be revisited after FW changes in january
+    #  2026. We also need to fix this on days when the sci Lut changes.
+    # After November 24th 2025 we need to do this step a different way.
+    date_switch = datetime.datetime(2025, 11, 24)
+    dataset_midpoint_ns = dataset["epoch"].values[dataset["epoch"].size // 2]
+    # Convert to datetime64 for comparison
+    dataset_midpoint = et_to_datetime64(ttj2000ns_to_et(dataset_midpoint_ns))
+    if dataset_midpoint < date_switch:
+        modes = (half_spin_per_esa_step > rgfo_half_spin) & (rgfo_half_spin > 0)
+    else:
+        # After November 24th, 2025, we no longer apply reduced geometric factors;
+        # always use the full geometric factor lookup.
+        modes = np.zeros_like(half_spin_per_esa_step, dtype=bool)
 
     # Get the geometric factors based on the modes
     gf = np.where(

imap_processing/tests/codice/test_codice_l2.py

@@ -91,14 +91,14 @@ def mock_half_spin_per_esa_step():
       ESA steps 0–63 belong to half_spin=1
       ESA steps 64–127 belong to half_spin=2
     """
-    return np.repeat([1, 2], 64)
+    return np.repeat([2, 3], 64)
 
 
 def test_compute_geometric_factors_all_full_mode(mock_half_spin_per_esa_step):
-    # rgfo_half_spin = 3 means all half_spin values (1 or 2) are < rgfo_half_spin
+    # rgfo_half_spin = 4 means all half_spin values (2 or 3) are < rgfo_half_spin
     dataset = xr.Dataset(
         {
-            "rgfo_half_spin": (("epoch",), np.array([3, 3])),
+            "rgfo_half_spin": (("epoch",), np.array([4, 4])),
             "half_spin_per_esa_step": (("esa_step",), mock_half_spin_per_esa_step),
         },
     )
@@ -113,11 +113,41 @@ def test_compute_geometric_factors_all_full_mode(mock_half_spin_per_esa_step):
     np.testing.assert_array_equal(result, expected)
 
 
+def test_compute_geometric_factors_past_nov_24th(mock_half_spin_per_esa_step):
+    # rgfo_half_spin = 1 means all half_spin values (>=2) are >= rgfo_half_spin
+    # Although the rgfo_half_spin indicates reduced mode, the date is past Nov 24th,
+    # 2024 so we expect full mode to be used.
+    dataset = xr.Dataset(
+        {
+            "rgfo_half_spin": (("epoch",), np.array([1, 1])),
+            "half_spin_per_esa_step": (
+                (
+                    "epoch",
+                    "esa_step",
+                ),
+                np.tile(mock_half_spin_per_esa_step, (2, 1)),
+            ),
+        },
+    )
+    geometric_factor_lut = {
+        "full": np.zeros((128, 24)),
+        "reduced": np.ones((128, 24)),
+    }
+    # Make sure epoch is past Nov 24th, 2024
+    ns_past_nov_24 = 900000000000000000
+    dataset = dataset.assign_coords({"epoch": np.repeat(ns_past_nov_24, 2)})
+    result = compute_geometric_factors(dataset, geometric_factor_lut)
+
+    # Expect "full" values everywhere
+    expected = np.full((2, 128, 24), 0)
+    np.testing.assert_array_equal(result, expected)
+
+
 def test_compute_geometric_factors_all_reduced_mode(mock_half_spin_per_esa_step):
-    # rgfo_half_spin = 0 means all half_spin values (>=1) are >= rgfo_half_spin
+    # rgfo_half_spin = 1 means all half_spin values (>=2) are >= rgfo_half_spin
     dataset = xr.Dataset(
         {
-            "rgfo_half_spin": (("epoch",), np.array([0])),
+            "rgfo_half_spin": (("epoch",), np.array([1])),
             "half_spin_per_esa_step": (("esa_step",), mock_half_spin_per_esa_step),
         },
     )
@@ -133,10 +163,10 @@ def test_compute_geometric_factors_all_reduced_mode(mock_half_spin_per_esa_step)
 
 
 def test_compute_geometric_factors_mixed(mock_half_spin_per_esa_step):
-    # rgfo_half_spin = 1
+    # rgfo_half_spin = 2
     dataset = xr.Dataset(
         {
-            "rgfo_half_spin": (("epoch",), np.array([1])),
+            "rgfo_half_spin": (("epoch",), np.array([2])),
             "half_spin_per_esa_step": (("esa_step",), mock_half_spin_per_esa_step),
         },
     )