def _get_blocks(self, n1, n2):
"""Wraps EEGFile._get_blocks to change the montage of the data"""
block = EEGFile._get_blocks(self, n1, n2)
new_block = self._block_descriptor.new(len(block))
for label, elec1, elec2 in self.indices:
new_block[label] = block[elec2] - block[elec1]
return new_block
def _cache_blocks(self, n2):
"""Cache the first n blocks if not already done"""
# Retrieve blocks
n1 = self._last_block
blockseg = EEGFile._get_blocks(self, n1, n2)
block_ind = len(self._blocksegments)
self._blocksegments.append((blockseg, n1))
for n in range(n1, n2):
self._blockrefs[n] = block_ind
self._last_block = n2
def _get_blocks(self, n1, n2):
block = EEGFile._get_blocks(self, n1, n2)
block_new = block.copy()
# Hopefully the filtering has previously ended on the block before
initial_states = self._filter_states.get(n1, self._zero_states)
final_states = []
for name, f, zi in zip(block.keys(), self._filters, initial_states):
x_old = block[name]
x_new, zf = self._apply_filter(x_old, f, zi)
block_new[name] = numpy.round(x_new)
final_states.append(zf)
self._filter_states[n2] = final_states
# Return as normal
return block_new
def _get_blocks(self, n1, n2):
"""Wraps EEGFile._get_block to return a different block"""
n1, n2 = [n + self._n1 for n in (n1, n2)]
return EEGFile._get_blocks(self, n1, n2)
