Initial revision

diff --git a/Demo/classes/bitvec.py b/Demo/classes/bitvec.py
new file mode 100755 (executable)
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+++ b/Demo/classes/bitvec.py
@@ -0,0 +1,341 @@
+#
+# 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
+
+error = 'bitvec.error'
+
+
+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 = 1L << l
+       if bitmask <= param:
+               raise 'FATAL', '(param, l) = ' + `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 = 0L
+               self._len = 0
+               if not len(params):
+                       pass
+               elif len(params) == 1:
+                       param, = params
+                       if type(param) == type([]):
+                               value = 0L
+                               bit_mask = 1L
+                               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(0L):
+                               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(0L):
+                               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 lenght indicates, truncating value'
+                                       self._data = self._data & \
+                                                 ((1L << length) - 1)
+                               self._len = length
+                       else:
+                               raise error, 'bitvec() requires array or long parameter'
+               else:
+                       raise error, 'bitvec() requires 0 -- 2 parameter(s)'
+
+               return self
+
+
+       def _init(self, data, len):
+               self._data = data
+               self._len = len
+               return self
+
+               
+       def append(self, item):
+               #_check_value(item)
+               #self[self._len:self._len] = [item]
+               self[self._len:self._len] = \
+                         BitVec()._init(long(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()._init(long(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, 0L
+               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 = ((1L << c) - 1) << (self._len - c)
+
+
+       def copy(self):
+               return BitVec()._init(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' + `self._data, self._len`
+
+       def __cmp__(self, other, *rest):
+               #rprt(`self`+'.__cmp__'+`(other, ) + rest`+'\n')
+               if type(other) != type(self):
+                       other = apply(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_lenght = 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(`self`+'.__len__()\n')
+               return self._len
+
+       def __getitem__(self, key):
+               #rprt(`self`+'.__getitem__('+`key`+')\n')
+               key = _check_key(self._len, key)
+               return self._data & (1L << key) != 0
+
+       def __setitem__(self, key, value):
+               #rprt(`self`+'.__setitem__'+`key, value`+'\n')
+               key = _check_key(self._len, key)
+               #_check_value(value)
+               if value:
+                       self._data = self._data | (1L << key)
+               else:
+                       self._data = self._data & ~(1L << key)
+
+       def __delitem__(self, key):
+               #rprt(`self`+'.__delitem__('+`key`+')\n')
+               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(`self`+'.__getslice__'+`i, j`+'\n')
+               i, j = _check_slice(self._len, i, j)
+               if i >= j:
+                       return BitVec()._init(0L, 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 & ((1L << nlength) - 1)
+               return BitVec()._init(ndata, nlength)
+
+       def __setslice__(self, i, j, sequence, *rest):
+               #rprt(`self`+'.__setslice__'+`(i, j, sequence) + rest`+'\n')
+               i, j = _check_slice(self._len, i, j)
+               if type(sequence) != type(self):
+                       sequence = apply(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(`self`+'.__delslice__'+`i, j`+'\n')
+               i, j = _check_slice(self._len, i, j)
+               if i == 0 and j == self._len:
+                       self._data, self._len = 0L, 0
+               elif i < j:
+                       self._data = self[:i]._data | (self[j:]._data >> i)
+                       self._len = self._len - j + i
+
+       def __add__(self, other):
+               #rprt(`self`+'.__add__('+`other`+')\n')
+               retval = self.copy()
+               retval[self._len:self._len] = other
+               return retval
+
+       def __mul__(self, multiplier):
+               #rprt(`self`+'.__mul__('+`multiplier`+')\n')
+               if type(multiplier) != type(0):
+                       raise TypeError, 'sequence subscript not int'
+               if multiplier <= 0:
+                       return BitVec()._init(0L, 0)
+               elif multiplier == 1:
+                       return self.copy()
+               #handle special cases all 0 or all 1...
+               if self._data == 0L:
+                       return BitVec()._init(0L, self._len * multiplier)
+               elif (~self)._data == 0L:
+                       return ~BitVec()._init(0L, self._len * multiplier)
+               #otherwise el cheapo again...
+               retval = BitVec()._init(0L, 0)
+               while multiplier:
+                       retval, multiplier = retval + self, multiplier - 1
+               return retval
+
+       def __and__(self, otherseq, *rest):
+               #rprt(`self`+'.__and__'+`(otherseq, ) + rest`+'\n')
+               if type(otherseq) != type(self):
+                       otherseq = apply(bitvec, (otherseq, ) + rest)
+               #sequence is now of our own type
+               return BitVec()._init(self._data & otherseq._data, \
+                         min(self._len, otherseq._len))
+
+
+       def __xor__(self, otherseq, *rest):
+               #rprt(`self`+'.__xor__'+`(otherseq, ) + rest`+'\n')
+               if type(otherseq) != type(self):
+                       otherseq = apply(bitvec, (otherseq, ) + rest)
+               #sequence is now of our own type
+               return BitVec()._init(self._data ^ otherseq._data, \
+                         max(self._len, otherseq._len))
+
+
+       def __or__(self, otherseq, *rest):
+               #rprt(`self`+'.__or__'+`(otherseq, ) + rest`+'\n')
+               if type(otherseq) != type(self):
+                       otherseq = apply(bitvec, (otherseq, ) + rest)
+               #sequence is now of our own type
+               return BitVec()._init(self._data | otherseq._data, \
+                         max(self._len, otherseq._len))
+
+
+       def __invert__(self):
+               #rprt(`self`+'.__invert__()\n')
+               return BitVec()._init(~self._data & ((1L << self._len) - 1), \
+                         self._len)
+
+       def __coerce__(self, otherseq, *rest):
+               #needed for *some* of the arithmetic operations
+               #rprt(`self`+'.__coerce__'+`(otherseq, ) + rest`+'\n')
+               if type(otherseq) != type(self):
+                       otherseq = apply(bitvec, (otherseq, ) + rest)
+               return self, otherseq
+
+       def __int__(self):
+               return int(self._data)
+
+       def __long__(self):
+               return long(self._data)
+
+       def __float__(self):
+               return float(self._data)
+
+
+def bitvec(params):
+       return apply(BitVec().init, params)