diff options
Diffstat (limited to 'Demo/classes/bitvec.py')
| -rw-r--r-- | Demo/classes/bitvec.py | 322 |
1 files changed, 0 insertions, 322 deletions
diff --git a/Demo/classes/bitvec.py b/Demo/classes/bitvec.py deleted file mode 100644 index 62b26cc..0000000 --- a/Demo/classes/bitvec.py +++ /dev/null @@ -1,322 +0,0 @@ -# -# this is a rather strict implementation of a bit vector class -# it is accessed the same way as an array of python-ints, except -# the value must be 0 or 1 -# - -import sys; rprt = sys.stderr.write #for debugging - -class error(Exception): - pass - - -def _check_value(value): - if type(value) != type(0) or not 0 <= value < 2: - raise error('bitvec() items must have int value 0 or 1') - - -import math - -def _compute_len(param): - mant, l = math.frexp(float(param)) - bitmask = 1 << l - if bitmask <= param: - raise ValueError('(param, l) = %r' % ((param, l),)) - while l: - bitmask = bitmask >> 1 - if param & bitmask: - break - l = l - 1 - return l - - -def _check_key(len, key): - if type(key) != type(0): - raise TypeError('sequence subscript not int') - if key < 0: - key = key + len - if not 0 <= key < len: - raise IndexError('list index out of range') - return key - -def _check_slice(len, i, j): - #the type is ok, Python already checked that - i, j = max(i, 0), min(len, j) - if i > j: - i = j - return i, j - - -class BitVec: - - def __init__(self, *params): - self._data = 0 - self._len = 0 - if not len(params): - pass - elif len(params) == 1: - param, = params - if type(param) == type([]): - value = 0 - bit_mask = 1 - for item in param: - # strict check - #_check_value(item) - if item: - value = value | bit_mask - bit_mask = bit_mask << 1 - self._data = value - self._len = len(param) - elif type(param) == type(0): - if param < 0: - raise error('bitvec() can\'t handle negative longs') - self._data = param - self._len = _compute_len(param) - else: - raise error('bitvec() requires array or long parameter') - elif len(params) == 2: - param, length = params - if type(param) == type(0): - if param < 0: - raise error('can\'t handle negative longs') - self._data = param - if type(length) != type(0): - raise error('bitvec()\'s 2nd parameter must be int') - computed_length = _compute_len(param) - if computed_length > length: - print('warning: bitvec() value is longer than the length indicates, truncating value') - self._data = self._data & \ - ((1 << length) - 1) - self._len = length - else: - raise error('bitvec() requires array or long parameter') - else: - raise error('bitvec() requires 0 -- 2 parameter(s)') - - - def append(self, item): - #_check_value(item) - #self[self._len:self._len] = [item] - self[self._len:self._len] = \ - BitVec(int(not not item), 1) - - - def count(self, value): - #_check_value(value) - if value: - data = self._data - else: - data = (~self)._data - count = 0 - while data: - data, count = data >> 1, count + (data & 1 != 0) - return count - - - def index(self, value): - #_check_value(value): - if value: - data = self._data - else: - data = (~self)._data - index = 0 - if not data: - raise ValueError('list.index(x): x not in list') - while not (data & 1): - data, index = data >> 1, index + 1 - return index - - - def insert(self, index, item): - #_check_value(item) - #self[index:index] = [item] - self[index:index] = BitVec(int(not not item), 1) - - - def remove(self, value): - del self[self.index(value)] - - - def reverse(self): - #ouch, this one is expensive! - #for i in self._len>>1: self[i], self[l-i] = self[l-i], self[i] - data, result = self._data, 0 - for i in range(self._len): - if not data: - result = result << (self._len - i) - break - result, data = (result << 1) | (data & 1), data >> 1 - self._data = result - - - def sort(self): - c = self.count(1) - self._data = ((1 << c) - 1) << (self._len - c) - - - def copy(self): - return BitVec(self._data, self._len) - - - def seq(self): - result = [] - for i in self: - result.append(i) - return result - - - def __repr__(self): - ##rprt('<bitvec class instance object>.' + '__repr__()\n') - return 'bitvec(%r, %r)' % (self._data, self._len) - - def __cmp__(self, other, *rest): - #rprt('%r.__cmp__%r\n' % (self, (other,) + rest)) - if type(other) != type(self): - other = bitvec(other, *rest) - #expensive solution... recursive binary, with slicing - length = self._len - if length == 0 or other._len == 0: - return cmp(length, other._len) - if length != other._len: - min_length = min(length, other._len) - return cmp(self[:min_length], other[:min_length]) or \ - cmp(self[min_length:], other[min_length:]) - #the lengths are the same now... - if self._data == other._data: - return 0 - if length == 1: - return cmp(self[0], other[0]) - else: - length = length >> 1 - return cmp(self[:length], other[:length]) or \ - cmp(self[length:], other[length:]) - - - def __len__(self): - #rprt('%r.__len__()\n' % (self,)) - return self._len - - def __getitem__(self, key): - #rprt('%r.__getitem__(%r)\n' % (self, key)) - key = _check_key(self._len, key) - return self._data & (1 << key) != 0 - - def __setitem__(self, key, value): - #rprt('%r.__setitem__(%r, %r)\n' % (self, key, value)) - key = _check_key(self._len, key) - #_check_value(value) - if value: - self._data = self._data | (1 << key) - else: - self._data = self._data & ~(1 << key) - - def __delitem__(self, key): - #rprt('%r.__delitem__(%r)\n' % (self, key)) - key = _check_key(self._len, key) - #el cheapo solution... - self._data = self[:key]._data | self[key+1:]._data >> key - self._len = self._len - 1 - - def __getslice__(self, i, j): - #rprt('%r.__getslice__(%r, %r)\n' % (self, i, j)) - i, j = _check_slice(self._len, i, j) - if i >= j: - return BitVec(0, 0) - if i: - ndata = self._data >> i - else: - ndata = self._data - nlength = j - i - if j != self._len: - #we'll have to invent faster variants here - #e.g. mod_2exp - ndata = ndata & ((1 << nlength) - 1) - return BitVec(ndata, nlength) - - def __setslice__(self, i, j, sequence, *rest): - #rprt('%s.__setslice__%r\n' % (self, (i, j, sequence) + rest)) - i, j = _check_slice(self._len, i, j) - if type(sequence) != type(self): - sequence = bitvec(sequence, *rest) - #sequence is now of our own type - ls_part = self[:i] - ms_part = self[j:] - self._data = ls_part._data | \ - ((sequence._data | \ - (ms_part._data << sequence._len)) << ls_part._len) - self._len = self._len - j + i + sequence._len - - def __delslice__(self, i, j): - #rprt('%r.__delslice__(%r, %r)\n' % (self, i, j)) - i, j = _check_slice(self._len, i, j) - if i == 0 and j == self._len: - self._data, self._len = 0, 0 - elif i < j: - self._data = self[:i]._data | (self[j:]._data >> i) - self._len = self._len - j + i - - def __add__(self, other): - #rprt('%r.__add__(%r)\n' % (self, other)) - retval = self.copy() - retval[self._len:self._len] = other - return retval - - def __mul__(self, multiplier): - #rprt('%r.__mul__(%r)\n' % (self, multiplier)) - if type(multiplier) != type(0): - raise TypeError('sequence subscript not int') - if multiplier <= 0: - return BitVec(0, 0) - elif multiplier == 1: - return self.copy() - #handle special cases all 0 or all 1... - if self._data == 0: - return BitVec(0, self._len * multiplier) - elif (~self)._data == 0: - return ~BitVec(0, self._len * multiplier) - #otherwise el cheapo again... - retval = BitVec(0, 0) - while multiplier: - retval, multiplier = retval + self, multiplier - 1 - return retval - - def __and__(self, otherseq, *rest): - #rprt('%r.__and__%r\n' % (self, (otherseq,) + rest)) - if type(otherseq) != type(self): - otherseq = bitvec(otherseq, *rest) - #sequence is now of our own type - return BitVec(self._data & otherseq._data, \ - min(self._len, otherseq._len)) - - - def __xor__(self, otherseq, *rest): - #rprt('%r.__xor__%r\n' % (self, (otherseq,) + rest)) - if type(otherseq) != type(self): - otherseq = bitvec(otherseq, *rest) - #sequence is now of our own type - return BitVec(self._data ^ otherseq._data, \ - max(self._len, otherseq._len)) - - - def __or__(self, otherseq, *rest): - #rprt('%r.__or__%r\n' % (self, (otherseq,) + rest)) - if type(otherseq) != type(self): - otherseq = bitvec(otherseq, *rest) - #sequence is now of our own type - return BitVec(self._data | otherseq._data, \ - max(self._len, otherseq._len)) - - - def __invert__(self): - #rprt('%r.__invert__()\n' % (self,)) - return BitVec(~self._data & ((1 << self._len) - 1), \ - self._len) - - def __int__(self): - return int(self._data) - - def __float__(self): - return float(self._data) - - -bitvec = BitVec |