Arrays.py
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Arrays.py
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			# This file is part of pybliographer
			#
			# Copyright (C) 1998-2006 Frederic GOBRY
			# Email : gobry@pybliographer.org
			#
			# This program is free software; you can redistribute it and/or
			# modify it under the terms of the GNU General Public License
			# as published by the Free Software Foundation; either version 2
			# of the License, or (at your option) any later version.
			#
			# This program is distributed in the hope that it will be useful,
			# but WITHOUT ANY WARRANTY; without even the implied warranty of
			# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
			# GNU General Public License for more details.
			#
			# You should have received a copy of the GNU General Public License
			# along with this program; if not, write to the Free Software
			# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
			#
			"""
			Result sets and indexes implemented on top of numpy arrays.

			"""

			import numpy

			from numpy import array, resize, zeros, fromstring

			from math import ceil, log

			from Pyblio.Store import Key

			def _to_power(size):
			""" Return the power of two immediately above 'size' """
			try:
			return 2 ** int(ceil(log(size, 2)))
			except OverflowError:
			return 1


			class KeyArray(object):
			""" A growing array of Pyblio keys. """

			def __init__(self, initial=1, a=None, s=None):

			if a is not None:
			self.a = a
			elif s is not None:
			self.a = fromstring(s, bool)
			else:
			self.a = zeros(_to_power(initial), bool)
			return

			def tostring(self):
			return self.a.tostring()

			def add(self, k):
			""" Set the key 'k' in the array """
			k -= 1

			try:
			self.a[k] = True
			except IndexError:
			c = len(self.a)

			largest = max(c, _to_power(k+1))
			self.a = resize(self.a, (largest,))
			self.a[c:] = False

			self.a[k] = True
			return

			def __delitem__(self, k):
			""" Remove key 'k' from the array """
			self.a[k-1] = False
			return

			def __len__(self):
			return numpy.sum(self.a)

			def __iter__(self):
			for key, status in enumerate(self.a):
			if status:
			yield Key(key + 1)
			return


			def match_arrays(a,b):
			""" Ensure a and b have the same size, enlarging the smallest of
			the two if needed."""

			la = len(a)
			lb = len(b)

			if la == lb:
			return a,b

			if la > lb:
			b = resize(b, la)
			b[lb:] = False

			elif lb > la:
			a = resize(a, lb)
			a[la:] = False

			return a, b

R3596/Pyblio/Arrays.py28d3c0f1dc2emaster

Arrays.pyView Options

R3596/Pyblio/Arrays.py
28d3c0f1dc2emaster

Arrays.py
View Options