Example #1
0
def generateNGramCandidatesToChange(sentence, MAX_NGRAMS):
    final_Sentence = ''
    token_position = 0
    for w, t in sentence:
        #if t not in ('NNP', 'NNPS') and token_position == 0:
        #final_Sentence=final_Sentence + ' ' + w.lower() + delim + t + delim + str(token_position)

        final_Sentence = final_Sentence + ' ' + w + delim + t + delim + str(
            token_position)
        token_position = token_position + 1
    #print final_Sentence.strip()
    candidates = OrderedDict()
    n = [i + 1 for i in xrange(MAX_NGRAMS)]
    for i in n:
        #print i
        nGrams = ngrams(final_Sentence.strip().split(), i)
        candidates[i] = list(nGrams)

    #total_candidates_to_change=sum(len(v) for v in candidates.itervalues())
    #print 'Total candidates that can be changed ~~ ',total_candidates_to_change

    paraphraseCandidateList = []
    for i in n:
        ngramlist = candidates[i]
        for ngram in ngramlist:
            #print ngrams
            candidateObject = CandidateObject(ngram, i)
            paraphraseCandidateList.append(candidateObject)
            #print candidateObject.wordObjectList[0].token
            #  sequence=' '.join(gram.split('/')[0] for gram in ngrams)
            #indices=[int(gram.split('/')[2]) for gram in ngrams]
            #print sequence, indices

    return paraphraseCandidateList
Example #2
0
    def nodecoords(tree, sentence, highlight):
        """
        Produce coordinates of nodes on a grid.

        Objective:

        - Produce coordinates for a non-overlapping placement of nodes and
            horizontal lines.
        - Order edges so that crossing edges cross a minimal number of previous
            horizontal lines (never vertical lines).

        Approach:

        - bottom up level order traversal (start at terminals)
        - at each level, identify nodes which cannot be on the same row
        - identify nodes which cannot be in the same column
        - place nodes into a grid at (row, column)
        - order child-parent edges with crossing edges last

        Coordinates are (row, column); the origin (0, 0) is at the top left;
        the root node is on row 0. Coordinates do not consider the size of a
        node (which depends on font, &c), so the width of a column of the grid
        should be automatically determined by the element with the greatest
        width in that column. Alternatively, the integer coordinates could be
        converted to coordinates in which the distances between adjacent nodes
        are non-uniform.

        Produces tuple (nodes, coords, edges, highlighted) where:

        - nodes[id]: Tree object for the node with this integer id
        - coords[id]: (n, m) coordinate where to draw node with id in the grid
        - edges[id]: parent id of node with this id (ordered dictionary)
        - highlighted: set of ids that should be highlighted
        """
        def findcell(m, matrix, startoflevel, children):
            """
            Find vacant row, column index for node ``m``.
            Iterate over current rows for this level (try lowest first)
            and look for cell between first and last child of this node,
            add new row to level if no free row available.
            """
            candidates = [a for _, a in children[m]]
            minidx, maxidx = min(candidates), max(candidates)
            leaves = tree[m].leaves()
            center = scale * sum(leaves) // len(leaves)  # center of gravity
            if minidx < maxidx and not minidx < center < maxidx:
                center = sum(candidates) // len(candidates)
            if max(candidates) - min(candidates) > 2 * scale:
                center -= center % scale  # round to unscaled coordinate
                if minidx < maxidx and not minidx < center < maxidx:
                    center += scale
            if ids[m] == 0:
                startoflevel = len(matrix)
            for rowidx in range(startoflevel, len(matrix) + 1):
                if rowidx == len(matrix):  # need to add a new row
                    matrix.append([
                        vertline if a not in (corner, None) else None
                        for a in matrix[-1]
                    ])
                row = matrix[rowidx]
                i = j = center
                if len(children[m]) == 1:  # place unaries directly above child
                    return rowidx, next(iter(children[m]))[1]
                elif all(a is None or a == vertline
                         for a in row[min(candidates):max(candidates) + 1]):
                    # find free column
                    for n in range(scale):
                        i = j = center + n
                        while j > minidx or i < maxidx:
                            if i < maxidx and (matrix[rowidx][i] is None
                                               or i in candidates):
                                return rowidx, i
                            elif j > minidx and (matrix[rowidx][j] is None
                                                 or j in candidates):
                                return rowidx, j
                            i += scale
                            j -= scale
            raise ValueError('could not find a free cell for:\n%s\n%s'
                             'min=%d; max=%d' %
                             (tree[m], minidx, maxidx, dumpmatrix()))

        def dumpmatrix():
            """Dump matrix contents for debugging purposes."""
            return '\n'.join('%2d: %s' % (n, ' '.join(('%2r' % i)[:2]
                                                      for i in row))
                             for n, row in enumerate(matrix))

        leaves = tree.leaves()
        if not all(isinstance(n, int) for n in leaves):
            raise ValueError('All leaves must be integer indices.')
        if len(leaves) != len(set(leaves)):
            raise ValueError('Indices must occur at most once.')
        if not all(0 <= n < len(sentence) for n in leaves):
            raise ValueError('All leaves must be in the interval 0..n '
                             'with n=len(sentence)\ntokens: %d indices: '
                             '%r\nsentence: %s' %
                             (len(sentence), tree.leaves(), sentence))
        vertline, corner = -1, -2  # constants
        tree = tree.copy(True)
        for a in tree.subtrees():
            a.sort(key=lambda n: min(n.leaves()) if isinstance(n, Tree) else n)
        scale = 2
        crossed = set()
        # internal nodes and lexical nodes (no frontiers)
        positions = tree.treepositions()
        maxdepth = max(map(len, positions)) + 1
        childcols = defaultdict(set)
        matrix = [[None] * (len(sentence) * scale)]
        nodes = {}
        ids = dict((a, n) for n, a in enumerate(positions))
        highlighted_nodes = set(n for a, n in ids.items()
                                if not highlight or tree[a] in highlight)
        levels = dict((n, []) for n in range(maxdepth - 1))
        terminals = []
        for a in positions:
            node = tree[a]
            if isinstance(node, Tree):
                levels[maxdepth - node.height()].append(a)
            else:
                terminals.append(a)

        for n in levels:
            levels[n].sort(
                key=lambda n: max(tree[n].leaves()) - min(tree[n].leaves()))
        terminals.sort()
        positions = set(positions)

        for m in terminals:
            i = int(tree[m]) * scale
            assert matrix[0][i] is None, (matrix[0][i], m, i)
            matrix[0][i] = ids[m]
            nodes[ids[m]] = sentence[tree[m]]
            if nodes[ids[m]] is None:
                nodes[ids[m]] = '...'
                highlighted_nodes.discard(ids[m])
            positions.remove(m)
            childcols[m[:-1]].add((0, i))

        # add other nodes centered on their children,
        # if the center is already taken, back off
        # to the left and right alternately, until an empty cell is found.
        for n in sorted(levels, reverse=True):
            nodesatdepth = levels[n]
            startoflevel = len(matrix)
            matrix.append([
                vertline if a not in (corner, None) else None
                for a in matrix[-1]
            ])
            for m in nodesatdepth:  # [::-1]:
                if n < maxdepth - 1 and childcols[m]:
                    _, pivot = min(childcols[m], key=itemgetter(1))
                    if (set(a[:-1] for row in matrix[:-1]
                            for a in row[:pivot] if isinstance(a, tuple)) &
                            set(a[:-1] for row in matrix[:-1]
                                for a in row[pivot:] if isinstance(a, tuple))):
                        crossed.add(m)

                rowidx, i = findcell(m, matrix, startoflevel, childcols)
                positions.remove(m)

                # block positions where children of this node branch out
                for _, x in childcols[m]:
                    matrix[rowidx][x] = corner
                # assert m == () or matrix[rowidx][i] in (None, corner), (
                #         matrix[rowidx][i], m, str(tree), ' '.join(sentence))
                # node itself
                matrix[rowidx][i] = ids[m]
                nodes[ids[m]] = tree[m]
                # add column to the set of children for its parent
                if m != ():
                    childcols[m[:-1]].add((rowidx, i))
        assert len(positions) == 0

        # remove unused columns, right to left
        for m in range(scale * len(sentence) - 1, -1, -1):
            if not any(isinstance(row[m], (Tree, int)) for row in matrix):
                for row in matrix:
                    del row[m]

        # remove unused rows, reverse
        matrix = [
            row for row in reversed(matrix)
            if not all(a is None or a == vertline for a in row)
        ]

        # collect coordinates of nodes
        coords = {}
        for n, _ in enumerate(matrix):
            for m, i in enumerate(matrix[n]):
                if isinstance(i, int) and i >= 0:
                    coords[i] = n, m

        # move crossed edges last
        positions = sorted([a for level in levels.values() for a in level],
                           key=lambda a: a[:-1] in crossed)

        # collect edges from node to node
        edges = OrderedDict()
        for i in reversed(positions):
            for j, _ in enumerate(tree[i]):
                edges[ids[i + (j, )]] = ids[i]

        return nodes, coords, edges, highlighted_nodes