def get_raster(self, starts, span, span_is_ms=True, return_ms=None, recs=None):
"""
:param starts: start points of each event (in samples, absolute unles recs is provided)
:param span: span of the raster (in samples or ms, depending on value of span_is_ms)
:param span_is_ms: whether the span of the raster is given in samples or ms, default is ms
:param return_ms: whether to return the raster in ms units, default is to do the units set by span_is_ms
:param recs: if recs is provided, starts are referred to the beginning of each rec
otherwise, the method will identify which rec each start belongs to and offset accordingly
:return: n x span
"""
if recs is None:
recs = kf.get_corresponding_rec(self.kwik_file, starts)
start_rec_offsets = kf.rec_start_array(self.kwik_file)
rec_list = kf.get_rec_list(self.kwik_file)
else:
assert(starts.size==recs.size)
rec_list = kf.get_rec_list(self.kwik_file)
start_rec_offsets = np.zeros_like(rec_list)
return_ms = span_is_ms if return_ms is None else return_ms
span_samples = np.int(span * self.sampling_rate * 0.001) if span_is_ms else span
span_ms = span if span_is_ms else np.int(span * 1000. / self.sampling_rate)
rows = starts.shape[0]
cols = span_ms if return_ms else span_samples
raster = np.empty((rows, cols), dtype=np.float64)
raster[:] = np.nan
# do the raster in samples
i_trial = 0
for rec in np.unique(recs):
rec_time_samples = self.time_samples[self.recordings==rec]
for start in starts[recs==rec]:
start-=start_rec_offsets[rec_list==rec]
end = np.int(start + span_samples)
where = (rec_time_samples[:] >= start) & (rec_time_samples[:] <= end)
n = np.sum(where)
raster[i_trial, :n] = rec_time_samples[where] - start
if return_ms:
raster[i_trial, :n] = np.round(raster[i_trial, :n] * 1000. / self.sampling_rate)
i_trial+=1
return raster
def get_rec_offsets(self):
self.recording_offsets = kf.rec_start_array(self.kwik_file)
return self.recording_offsets