Fix bug when 2 signals in a pair are not perfectly aligned for wavelet coherence (#232)

Add length of signal to the wavelet caching key.

There are cases where 2 signals in a pair are not exactly the same
length (one sample of difference). In these cases the longest signal is
cropped. But when computing intra, we reuse the same signal (not from
the pair), so we should load a cropped cached signal.

Author: patricefortin

hypyp/wavelet/base_wavelet.py

@@ -424,9 +424,12 @@ def _get_cache_key_pair(self, pair: PairSignals, subject_idx: int, obj_id: str,
         if subject_idx == 0:
             subject_label = pair.label_s1
             ch_name = pair.label_ch1
+            # include signal length in key because it might have been croped to align y1 and y2 
+            n = len(pair.y1)
         elif subject_idx == 1:
             subject_label = pair.label_s2
             ch_name = pair.label_ch2
+            n = len(pair.y2)
         else:
             raise RuntimeError(f'subject_idx must be 0 or 1')
 
@@ -437,7 +440,7 @@ def _get_cache_key_pair(self, pair: PairSignals, subject_idx: int, obj_id: str,
             raise RuntimeError(f'must have task to have unique identifiers in caching')
 
         time_range_str = f'{pair.x[0]}-{pair.x[-1]}'
-        key = f'[{subject_label}][{ch_name}][{pair.label_task}][{pair.epoch_idx}][{pair.x[0]}-{pair.x[-1]}][{time_range_str}][{obj_id}]'
+        key = f'[{subject_label}][{ch_name}][{pair.label_task}][{pair.epoch_idx}][{n}][{pair.x[0]}-{pair.x[-1]}][{time_range_str}][{obj_id}]'
         if cache_suffix != '':
             key += f'_{cache_suffix}'