ENH: repoint mid-time utils function (#2167)

Author: tech3371

imap_processing/spice/repoint.py

@@ -9,6 +9,8 @@
 from numpy import typing as npt
 
 from imap_processing.spice import config
+from imap_processing.spice.geometry import imap_state
+from imap_processing.spice.time import met_to_sclkticks, sct_to_et
 
 logger = logging.getLogger(__name__)
 
@@ -221,3 +223,50 @@ def get_pointing_times(met_time: float) -> tuple[float, float]:
     ][0]
     pointing_end_met = repoint_df["repoint_start_met"].iloc[pointing_idx + 1].item()
     return pointing_start_met, pointing_end_met
+
+
+def get_pointing_mid_time(met_time: float) -> float:
+    """
+    Get mid-point of the pointing for the given MET time.
+
+    Get the mid-point time between the end of one repoint and
+    start of the next. Input could be a MET time.
+
+    Parameters
+    ----------
+    met_time : float
+        The MET time in a repoint.
+
+    Returns
+    -------
+    repoint_mid_time : float
+        The mid MET time of the repoint maneuver.
+    """
+    pointing_start_met, pointing_end_met = get_pointing_times(met_time)
+    return (pointing_start_met + pointing_end_met) / 2
+
+
+def get_mid_point_state(met_time: float) -> npt.NDArray:
+    """
+    Get IMAP state for the mid-point.
+
+    Get IMAP state for the mid-point of the pointing in
+    reference frame, ECLIPJ2000 and observer, SUN.
+
+    Parameters
+    ----------
+    met_time : float
+        The MET time in a pointing.
+
+    Returns
+    -------
+    mid_point_state : numpy.ndarray
+        The mid state of the pointing maneuver.
+    """
+    # Get mid point time in ET
+    mid_point_time = get_pointing_mid_time(met_time)
+    mid_point_time_et = sct_to_et(met_to_sclkticks(mid_point_time))
+
+    # Convert mid point time to state
+    pointing_state = imap_state(mid_point_time_et)
+    return pointing_state

imap_processing/tests/spice/test_repoint.py

@@ -1,6 +1,7 @@
 """Test coverage for imap_processing.spice.repoint.py"""
 
 from pathlib import Path
+from unittest import mock
 
 import numpy as np
 import pandas as pd
@@ -81,6 +82,38 @@ def test_get_pointing_times(fake_repoint_data):
     assert pointing_end_time == expected_times[1]
 
 
+def test_get_pointing_mid_time(fake_repoint_data, monkeypatch):
+    """Test coverage for get_pointing_mid_time function."""
+    times = 6
+    expected_times = (5.1, 15.2)
+
+    expected_mid_time = np.mean(expected_times)
+
+    mid_time = repoint.get_pointing_mid_time(times)
+
+    assert mid_time == expected_mid_time
+
+
+@pytest.mark.external_kernel
+@mock.patch("imap_processing.spice.repoint.imap_state")
+@mock.patch("imap_processing.spice.repoint.get_pointing_times")
+def test_mid_point_state(mock_get_pointing_times, mock_imap_state, furnish_kernels):
+    """Test coverage for imap_state()"""
+    met = 5
+    mock_get_pointing_times.return_value = (5.1, 15.2)
+    # Mock the imap_state function
+    mock_imap_state.return_value = np.array(
+        [1.0, 2.0, 3.0, 0.1, 0.2, 0.3],  # Example position and velocity data
+    )
+    kernels = [
+        "naif0012.tls",
+        "imap_sclk_0000.tsc",
+    ]
+    with furnish_kernels(kernels):
+        state = repoint.get_mid_point_state(met)
+        assert state.shape == (6,)
+
+
 @pytest.mark.parametrize(
     "query_times, match_str",
     [