Look into the template option.

Author: JoeZiminski

src/spikeinterface/working/load_kilosort_utils.py

@@ -119,54 +119,27 @@ def _get_locations_from_pc_features(params):
 
     Notes
     -----
-    Location of of each individual spike is computed from its low-dimensional projection.
-    During sorting, kilosort computes the '
-    `pc_features` (num_spikes, num_PC, num_channels) holds the PC values for each spike.
-    Taking the first component, the subset of 32 channels associated with this
-    spike  are indexed to get the actual channel locations (in um). Then, the channel
-    locations are weighted by their PC values.
+    My understanding so far. KS1 paper; The individual spike waveforms are decomposed into
+    'private PCs'. Let the waveform matrix W be time (t) x channel (c). PCA
+    decompoisition is performed to compute c basis waveforms. Scores for each
+    channel onto the top three PCs are stored (these recover the waveform well.
 
     This function is based on code in Nick Steinmetz's `spikes` repository,
     https://github.com/cortex-lab/spikes
     """
-    # Compute spike depths
-
-    # for each spike, a PCA is computed just on that spike (n samples x n channels).
-    # the components are all different between spikes, so are not saved.
-    # This gives a (n pc = 3, num channels) set of scores.
-    # but then how it is possible for some spikes to have zero score onto the principal channel?
-
-    breakpoint()
-    pc_features = params["pc_features"][:, 0, :]
+    pc_features = params["pc_features"][:, 0, :].copy()
     pc_features[pc_features < 0] = 0
 
-    # Some spikes do not load at all onto the first PC. To avoid biasing the
-    # dataset by removing these, we repeat the above for the next PC,
-    # to compute distances for neurons that do not load onto the 1st PC.
-    # This is not ideal at all, it would be much better to a) find the
-    # max value for each channel on each of the PCs (i.e. basis vectors).
-    # Then recompute the estimated waveform peak on each channel by
-    # summing the PCs by their respective weights. However, the PC basis
-    # vectors themselves do not appear to be output by KS.
-
-    # We include the (n_channels i.e. features) from the second PC
-    # into the `pc_features` mostly containing the first PC. As all
-    # operations are per-spike (i.e. row-wise)
-    no_pc1_signal_spikes = np.where(np.sum(pc_features, axis=1) == 0)
-
-    pc_features_2 = params["pc_features"][:, 1, :]
-    pc_features_2[pc_features_2 < 0] = 0
-
-    pc_features[no_pc1_signal_spikes] = pc_features_2[no_pc1_signal_spikes]
-
     if np.any(np.sum(pc_features, axis=1) == 0):
+        # TODO: 1) handle this case for pc_features
+        #       2) instead use the template_features for all other versions.
         raise RuntimeError(
             "Some spikes do not load at all onto the first"
             "or second principal component. It is necessary"
             "to extend this code section to handle more components."
         )
 
-    # Get the channel indices corresponding to the 32 channels from the PC.
+    # Get the channel indices corresponding to the channels from the PC.
     spike_features_indices = params["pc_features_indices"][params["spike_templates"], :]
 
     # Compute the spike locations as the center of mass of the PC scores
@@ -343,8 +316,15 @@ def load_ks_dir(sorter_output: Path, exclude_noise: bool = True, load_pcs: bool
     if load_pcs:
         pc_features = np.load(sorter_output / "pc_features.npy")
         pc_features_indices = np.load(sorter_output / "pc_feature_ind.npy")
+
+        if (sorter_output / "template_features.npy").is_file():
+            template_features = np.load(sorter_output / "template_features.npy")
+            template_features_indices = np.load(sorter_output / "templates_ind.npy")
+        else:
+            template_features = template_features_indices = None
     else:
         pc_features = pc_features_indices = None
+        template_features = template_features_indices = None
 
     # This makes the assumption that there will never be different .csv and .tsv files
     # in the same sorter output (this should never happen, there will never even be two).
@@ -364,6 +344,8 @@ def load_ks_dir(sorter_output: Path, exclude_noise: bool = True, load_pcs: bool
 
         if load_pcs:
             pc_features = pc_features[not_noise_clusters_by_spike, :, :]
+            if template_features is not None:
+                template_features = template_features[not_noise_clusters_by_spike, :, :]
 
         spike_clusters = spike_clusters[not_noise_clusters_by_spike]
         cluster_ids = cluster_ids[cluster_groups != 0]
@@ -378,6 +360,8 @@ def load_ks_dir(sorter_output: Path, exclude_noise: bool = True, load_pcs: bool
         "spike_clusters": spike_clusters.squeeze(),
         "pc_features": pc_features,
         "pc_features_indices": pc_features_indices,
+        "template_features": template_features,
+        "template_features_indices": template_features_indices,
         "temp_scaling_amplitudes": temp_scaling_amplitudes.squeeze(),
         "cluster_ids": cluster_ids,
         "cluster_groups": cluster_groups,