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#
# Copyright 2003,2004 Free Software Foundation, Inc.
#
# This file is part of GNU Radio
#
# SPDX-License-Identifier: GPL-3.0-or-later
#
#
# misc utilities
import types
class seq_with_cursor (object):
__slots__ = [ 'items', 'index' ]
def __init__ (self, items, initial_index = None, initial_value = None):
assert len (items) > 0, "seq_with_cursor: len (items) == 0"
self.items = items
self.set_index (initial_index)
if initial_value is not None:
self.set_index_by_value(initial_value)
def set_index (self, initial_index):
if initial_index is None:
self.index = len (self.items) / 2
elif initial_index >= 0 and initial_index < len (self.items):
self.index = initial_index
else:
raise ValueError
def set_index_by_value(self, v):
"""
Set index to the smallest value such that items[index] >= v.
If there is no such item, set index to the maximum value.
"""
self.set_index(0) # side effect!
cv = self.current()
more = True
while cv < v and more:
cv, more = next(self) # side effect!
def __next__ (self):
new_index = self.index + 1
if new_index < len (self.items):
self.index = new_index
return self.items[new_index], True
else:
return self.items[self.index], False
def prev (self):
new_index = self.index - 1
if new_index >= 0:
self.index = new_index
return self.items[new_index], True
else:
return self.items[self.index], False
def current (self):
return self.items[self.index]
def get_seq (self):
return self.items[:] # copy of items
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