laydi/workflows/gobrowser.py

import gtk
from fluents import dataset, logger, plots, workflow, fluents, project, view, main
import geneontology
from matplotlib.nxutils import points_inside_poly
import matplotlib
#from scipy import array, randn, log, ones, zeros
from scipy import *
from numpy import matlib
import networkx
import re
import rpy

EVIDENCE_CODES=[('IMP', 'Inferred from mutant phenotype'),
                ('IGI', 'Inferred from genetic interaction'),
                ('IPI', 'Inferred from physical interaction'),
                ('ISS', 'Inferred from sequence or structure similarity'),
                ('IDA', 'Inferred from direct assay'),
                ('IEP', 'Inferred on expression pattern'),
                ('IEA', 'Inferred from electronic annotation'),
                ('TAS', 'Traceable author statement'),
                ('NAS', 'Non-traceable author statement'),
                ('ND', 'No biological data available'),
                ('RCA', 'Inferred from reviewed computational analysis'),
                ('IC', 'Inferred by curator')]
            
DISTANCE_METRICS = [('resnik', 'Resnik'), 
                    ('jiang', 'Jiang & Conrath'),
                    ('fussimeg', 'FuSSiMeG')]

GO_DATA_DIR = '/home/einarr/data'

evidence = None
go = None

class GoTermView (gtk.Frame):

    def __init__(self):
        gtk.Frame.__init__(self)
        tab = gtk.Table(2, 3, False)
        self._table = tab
        
        self._name = gtk.Label('')
        self._name.set_line_wrap(True)
        self._name.set_alignment(0, 0)
        name_label = gtk.Label('Name:')
        name_label.set_alignment(0, 0)
        tab.attach(name_label, 0, 1, 0, 1, gtk.FILL, gtk.FILL, 5, 5)
        tab.attach(self._name, 1, 2, 0, 1, gtk.FILL|gtk.EXPAND, gtk.FILL, 5, 5)
        
        self._isa_parents = gtk.HBox()
        isa_parents_label = gtk.Label('Is a:')
        tab.attach(isa_parents_label, 0, 1, 1, 2, gtk.FILL, gtk.FILL, 5, 5)
        tab.attach(self._isa_parents, 1, 2, 1, 2, gtk.FILL, gtk.FILL, 5, 5)
        
        self._def = gtk.TextBuffer()
        textview = gtk.TextView(self._def)
        textview.set_wrap_mode(gtk.WRAP_WORD)
        scrolled_window = gtk.ScrolledWindow()
        scrolled_window.add(textview)
        def_label = gtk.Label('Def:')
        def_label.set_alignment(0.0, 0.0)
        tab.attach(def_label, 0, 1, 2, 3, gtk.FILL, gtk.FILL, 5, 5)
        tab.attach(scrolled_window, 1, 2, 2, 3, gtk.FILL|gtk.EXPAND, gtk.FILL|gtk.EXPAND, 5, 5)
        
        self._tab = tab
        self.add(tab)
        self.set_go_term(None)

    def set_go_term(self, term):
        if term:
            self.set_label(term['id'])
            self._name.set_text(term['name'])
            self._def.set_text(term['def'])
            self._tab.remove(self._isa_parents)
            self._isa_parents = gtk.HBox()
            for p in term['is_a']:
                btn = gtk.Button(p)
                btn.show()
                self._isa_parents.add(btn)
            self._isa_parents.show()
            self._tab.attach(self._isa_parents, 1, 2, 1, 2, gtk.FILL, gtk.FILL, 5, 5)
        else:
            self.set_label('GO Term')
            self._name.set_text('')
            self._def.set_text('')
            self._tab.remove(self._isa_parents)
            self._isa_parents = gtk.HBox()
            self._tab.attach(self._isa_parents, 1, 2, 1, 2, gtk.FILL, gtk.FILL, 5, 5)
        

class GeneOntologyTree (gtk.HPaned):
    
    def __init__(self, network):
        gtk.HPaned.__init__(self)
        self.set_position(400)
    
        treemodel = geneontology.get_go_treestore(network)
        self._treemodel = treemodel
        self._tree_view = gtk.TreeView(treemodel)

        self._selected_terms = set()

        self._tree_view.set_fixed_height_mode(True)

        # Set up context menu
        self._context_menu = GoTermContextMenu(treemodel, self._tree_view)
        self._tree_view.connect('popup_menu', self._popup_menu)
        self._tree_view.connect('button_press_event', self._on_button_press)

        renderer = gtk.CellRendererText()
        go_column = gtk.TreeViewColumn('GO ID', renderer, text=0)
        go_column.set_sizing(gtk.TREE_VIEW_COLUMN_FIXED)
        go_column.set_fixed_width(200)
        go_column.set_resizable(True)
        self._tree_view.insert_column(go_column, 0)

        renderer = gtk.CellRendererToggle()
        renderer.set_property('activatable', True)
        renderer.connect('toggled', self._toggle_selected)
        renderer.set_active(True)
        renderer.set_property('mode', gtk.CELL_RENDERER_MODE_ACTIVATABLE)
        go_column = gtk.TreeViewColumn('T', renderer, active=2)
        go_column.set_fixed_width(20)
        go_column.set_sizing(gtk.TREE_VIEW_COLUMN_FIXED)
        go_column.set_resizable(True)
        self._tree_view.insert_column(go_column, 1)

        renderer = gtk.CellRendererText()
        go_column = gtk.TreeViewColumn('Name', renderer, text=1)
        go_column.set_fixed_width(200)
        go_column.set_sizing(gtk.TREE_VIEW_COLUMN_FIXED)
        go_column.set_resizable(True)
        self._tree_view.insert_column(go_column, 2)

        self._desc_view = GoTermView()

        self._tree_view.connect('cursor-changed', self._on_cursor_changed)

        scrolled_window = gtk.ScrolledWindow()
        scrolled_window.add(self._tree_view)
        self.add1(scrolled_window)
        self.add2(self._desc_view)
        self.show_all()

    def _on_cursor_changed(self, tree):
        path, col = self._tree_view.get_cursor()
        current = self._treemodel.get_iter(path)
        term = self._treemodel.get_value(current, 3)
        self._desc_view.set_go_term(term)        
        

    ##
    ## GTK Callback functions
    ##
    def _popup_menu(self, *rest):
        self.menu.popup(None, None, None, 0, 0)

    def _on_button_press(self, widget, event):
        path = widget.get_path_at_pos(int(event.x), int(event.y))
        iter = None

        if path:
            iter = self._treemodel.get_iter(path[0])
            obj = self._treemodel.get_value(iter, 3)
        else:
            obj = None

        self._context_menu.set_current_term(obj, iter)

        if event.button == 3:
            self._context_menu.popup(None, None, None, event.button, event.time)

    def _toggle_selected(self, renderer, path):
        iter = self._treemodel.get_iter(path)
        
        selected = self._treemodel.get_value(iter, 2)
        id = self._treemodel.get_value(iter, 0)

        self._treemodel.set_value(iter, 2, not selected)

        if selected:
            self._selected_terms.remove(id)
        else:
            self._selected_terms.add(id)


class GoTermContextMenu (gtk.Menu):
    """Context menu for GO terms in the gene ontology browser"""

    def __init__(self, treemodel, treeview):
        self._treemodel = treemodel
        self._treeview = treeview
        self._current_term = None
        self._current_iter = None

        gtk.Menu.__init__(self)

        # Popuplate tree
        self._expand_item = i = gtk.MenuItem('Expand')
        i.connect('activate', self._on_expand_subtree, treemodel, treeview)
        self.append(i)
        i.show()

        self._collapse_item = i = gtk.MenuItem('Collapse')
        i.connect('activate', self._on_collapse_subtree, treemodel, treeview)
        self.append(i)
        i.show()

        self._select_subtree_item = i = gtk.MenuItem('Select subtree')
        i.connect('activate', self._on_select_subtree, treemodel, treeview)
        self.append(i)
        i.show()

    def set_current_term(self, term, it):
        self._current_term = term
        self._current_iter = it

    def _on_expand_subtree(self, item, treemodel, treeview):
        path = treemodel.get_path(self._current_iter)
        treeview.expand_row(path, True)

    def _on_collapse_subtree(self, item, treemodel, treeview):
        treeview.collapse_row(treemodel.get_path(self._current_iter))

    def _on_select_subtree(self, item, treemodel, treeview):
        logger.log('notice', 'Selecting subtree from GO id: %s (%s)' %
                   (self._current_term['id'], self._current_term['name']))
        ids = [x['id'] for x in networkx.bfs(go, self._current_term)]
        project.project.set_selection('go-terms', set(ids))


class LoadGOFunction(workflow.Function): 
    def __init__(self):
        workflow.Function.__init__(self, 'load-go', 'Load Gene Ontology')

    def run(self):
        global go
        if go:
            return

        go = geneontology.read_default_go()
        browser = GeneOntologyTree(go)
        label = gtk.Label('_Gene Ontology')
        label.set_use_underline(True)
        fluents.app['bottom_notebook'].append_page(browser, label)

class LoadAnnotationsFunction(workflow.Function):

    def __init__(self):
        workflow.Function.__init__(self, 'load-go-ann', 'Load Annotations')
        self.annotations = None
    
    def run(self):
        global evidence
        f = open(GO_DATA_DIR + '/goa-condensed')
        ev_codes = f.readline().split()
        go_terms = []
    
        lines = f.readlines()
        m = zeros((len(lines), len(ev_codes)))

        for i, l in enumerate(lines):
            values = l.split()
            go_terms.append(values[0])
            for j, v in enumerate(values[1:]):
                m[i,j] = float(v.strip())
        
        d = dataset.Dataset(m, 
                            [['go-terms', go_terms], ['evidence', ev_codes]],
                            name='GO evidence')

        evidence = d
        return [d]
            

class GOWeightDialog(gtk.Dialog):
    def __init__(self):
        gtk.Dialog.__init__(self, 'GO Gene List Influence',
                            None,
                            gtk.DIALOG_MODAL | gtk.DIALOG_DESTROY_WITH_PARENT,
                            (gtk.STOCK_OK, gtk.RESPONSE_OK,
                             gtk.STOCK_CANCEL, gtk.RESPONSE_CANCEL))

        table = gtk.Table(2, 2)
        
        sim_lbl = gtk.Label('Similarity threshold: ')
        table.attach(sim_lbl, 0, 1, 0, 1)
        adjustment = gtk.Adjustment(0, 0, 10, 0.1, 1.0, 1.0)
        sim_spin = gtk.SpinButton(adjustment, 0.0, 2)
        table.attach(sim_spin, 1, 2, 0, 1)

        rank_lbl = gtk.Label('Rank threshold: ')
        table.attach(rank_lbl, 0, 1, 1, 2)
        rank_adj = gtk.Adjustment(0, 0, 10, 0.1, 1.0, 1.0)
        rank_spin = gtk.SpinButton(rank_adj, 0.0, 2)
        table.attach(rank_spin, 1, 2, 1, 2)
        
        sim_lbl.show()
        sim_spin.show()
        rank_lbl.show()
        rank_spin.show()
        
        table.show()
        self.vbox.add(table)
        self._sim_spin = sim_spin
        self._rank_spin = rank_spin

    def set_options(self, options):
        self._sim_spin.set_value(options['similarity_threshold'])
        self._rank_spin.set_value(options['rank_threshold'])

    def set_editable(self, editable):
        self._sim_spin.set_sensitive(editable)
        self._rank_spin.set_sensitive(editable)

    def update_options(self, options):
        options['similarity_threshold'] = self._sim_spin.get_value()
        options['rank_threshold'] = self._rank_spin.get_value()
        

class DistanceToSelectionFunction(workflow.Function):
    def __init__(self):
        workflow.Function.__init__(self, 'dist-to-sel', 'Dist. to Selection')
        self.options = DistanceToSelectionOptions()

    def run(self, similarities, selection):
        self.show_gui(similarities, self.options)

        retval = []

        dims = similarities.get_dim_name()
        if dims[0] != "_%s" %dims[1] and dims[1] != "_%s" %dims[0]:
            logger.log('warning', 'Are you sure this is a similarity matrix?')

        dim = dims[0]
        print "dim", dim
       
        print "selection", selection[dim]
        print "indices", similarities.get_indices(dim, selection[dim])
        indices = similarities.get_indices(dim, selection[dim])
        m = apply_along_axis(max, 1, similarities.asarray().take(indices, 1))
        retval.append(dataset.Dataset(m, [(dim, similarities[dim]),
                                          ("_dummy", '0')]))
        
        return retval

    def show_gui(self, similarities, options, edit=True):
        dialog = DistanceToSelectionOptionsDialog([similarities], self.options)
        response = dialog.run()
        dialog.hide()
        if response == gtk.RESPONSE_OK:
            dialog.set_output()
            return dialog.get_options()
        else:
            return options

class GOWeightFunction(workflow.Function):
    def __init__(self):
        workflow.Function.__init__(self, 'load-go-ann', 'GO Influence')
        self.options = GOWeightOptions()
    
    def run(self, genelist, similarity):
        ## Show dialog box
        self.show_gui(self.options)

        ## assure that data is "correct", i.e., that we can perform
        ## the desired operations.
        common_dims = genelist.common_dims(similarity)
        if len(common_dims) == 0:
            logger.log('error', 'No common dimension in the selected datasets.')
        elif len(common_dims) > 1:
            logger.log('error', "More than one common dimension in the " +
                       "selected datasets. Don't know what to do.")
        gene_dim = common_dims[0]
        logger.log('debug', 'Assuming genes are in dimension: %s' % gene_dim)

        ## Do the calculations.
        d = {}
        
        
    def show_gui(self, options, edit=True):
        dialog = GOWeightDialog()
        dialog.set_options(self.options)
        dialog.show_all()
        dialog.set_editable(edit)
        response = dialog.run()
        dialog.hide()
        if response == gtk.RESPONSE_OK:
            return dialog.update_options(self.options)
        else:
            return options


class DistanceToSelectionOptionsDialog(workflow.OptionsDialog):
    def __init__(self, data, options):
        workflow.OptionsDialog.__init__(self, data, options, ['X'])

                                        
class TTestOptionsDialog(workflow.OptionsDialog):

    def __init__(self, data, options):
	workflow.OptionsDialog.__init__(self, data, options,
                                        ['X', 'Categories'])

        vb = gtk.VBox()
        l = gtk.Label("Limit")
        adj = gtk.Adjustment(0, 0.0, 1.0, 0.01, 1.0, 1.0)
        sb = gtk.SpinButton(adj, 0.0, 2)
        l.show()
        sb.show()

        vb.add(l)
        vb.add(sb)
        vb.show()
        self.nb.insert_page(vb, gtk.Label("Limit"), -1)


class TTestFunction(workflow.Function):
    def __init__(self):
        workflow.Function.__init__(self, 't-test', 't-test')
        self.options = TTestOptions()

    def run(self, x, categories):
        self.show_gui(x, categories)

        retval = []
        m = x.asarray()
        c = categories.asarray()

        # Nonsmokers and current smokers
        ns = m.take(nonzero(c[:,0]), 0)[0]
        cs = m.take(nonzero(c[:,2]), 0)[0]

        tscores = stats.ttest_ind(ns, cs)

        print "Out data:", self.options['out_data']
        tds = dataset.Dataset(tscores[0], [('gene_id', x['gene_id']), 
                                           ('_t', ['0'])],
                              name='t-values')
        if 't-value' in self.options['out_data']:
            retval.append(tds)
            
        pds = dataset.Dataset(tscores[1], [('gene_id', x['gene_id']), 
                                           ('_p', ['0'])],
                              name='p-values')
        if 'p-value' in self.options['out_data']:
            retval.append(pds)
            
        if ProbabilityHistogramPlot in self.options['out_plots']:
            retval.append(ProbabilityHistogramPlot(pds))

        if VolcanoPlot in self.options['out_plots']:
            fc = apply_along_axis(mean, 0, ns) / apply_along_axis(mean, 0, cs)
            fcds = dataset.Dataset(fc, [('gene_id', x['gene_id']),
                                        ('_dummy', ['0'])],
                                   name="Fold change")

            retval.append(VolcanoPlot(fcds, pds, 'gene_id'))

        return retval

    def show_gui(self, x, categories):
        dialog = TTestOptionsDialog([x, categories], self.options)
        response = dialog.run()
        dialog.hide()
        if response == gtk.RESPONSE_OK:
            dialog.set_output()
            return dialog.get_options()
        else:
            return options


class SetICFunction(workflow.Function):
    def __init__(self):
        workflow.Function.__init__(self, 'set-ic', 'Set IC')

    def run(self, ds):
        if 'go-terms' in ds.get_dim_name():
            main.workflow.current_ic = ds
        else:
            logger.log('warning', 'Cannot use this dataset as IC on the go-terms dimension')
        return
        
class PlotDagFunction(workflow.Function):
    def __init__(self):
        workflow.Function.__init__(self, 'go-dag', 'Build DAG')

    def run(self, selection):
        g = self.get_network(list(selection['go-terms']))
        ds = dataset.GraphDataset(networkx.adj_matrix(g),
                                  [('go-terms', g.nodes()), ('_go-terms', g.nodes())],
                                  name="DAG")
        return [DagPlot(g)]

    def get_network(self, terms, subtree='bp'):
        """Returns a DAG connecting the given terms by including their parents
        up to the level needed to connect them. The subtree parameter is one of
           mf - molecular function
           bp - biological process
           cc - cellular component"""

        rpy.r.library("GOstats")
    
        if subtree == 'mf':
            subtree_r = rpy.r.GOMFPARENTS
        elif subtree == 'bp':
            subtree_r = rpy.r.GOBPPARENTS
        elif subtree == 'cc':
            subtree_r = rpy.r.GOCCPARENTS
        else:
            raise Exception("Unknown subtree. Use mf, bp or cc.")
        
        g = rpy.r.GOGraph(terms, subtree_r)
        edges = rpy.r.edges(g)
    
        nxgraph = networkx.DiGraph()
        for child, d in edges.items():
            for parent in d.keys():
                nxgraph.add_edge(parent, child)

        return nxgraph
    

class TTestOptions(workflow.Options):

    def __init__(self):
        workflow.Options.__init__(self)
        self['all_plots'] = [(ProbabilityHistogramPlot, 'Histogram', True),
                             (VolcanoPlot, 'Histogram', True)]
        self['all_data'] = [('t-value', 't-values', True),
                            ('p-value', 'Probabilities', True),
                            ('categories', 'Categories', False)]
        self['out_data'] = ['t-value', 'p-value']


class DistanceToSelectionOptions(workflow.Options):
    def __init__(self):
        workflow.Options.__init__(self)
        self['all_data'] = [('mindist', 'Minimum distance', True)]

        
class GOWeightOptions(workflow.Options):
    def __init__(self):
        workflow.Options.__init__(self)
        self['similarity_threshold'] = 0.0
        self['rank_threshold'] = 0.0

class ProbabilityHistogramPlot(plots.HistogramPlot):
    def __init__(self, ds):
        plots.HistogramPlot.__init__(self, ds, name="Confidence", bins=50)


class VolcanoPlot(plots.ScatterPlot):
    def __init__(self, fold_ds, p_ds, dim, **kw):
        plots.ScatterPlot.__init__(self, fold_ds, p_ds, 'gene_id', '_dummy', 
                                   '0', '0',
                                   name="Volcano plot", 
                                   sel_dim_2='_p', **kw)

    
class DagPlot(plots.Plot):
    def __init__(self, graph, dim='go-terms', pos=None, nodecolor='b', nodesize=40,
                 with_labels=False, name='DAG Plot'):

        plots.Plot.__init__(self, name)
        self._add_ic_spin_buttons()
        self.nodes = graph.nodes()
        self.graph = graph
        self._pos = pos
        self._nodesize = nodesize
        self._nodecolor = nodecolor
        self._with_labels = with_labels
        self.visible = set()
        
        self.current_dim = dim

        if not self._pos:
            self._pos = self._calc_pos(graph)
        self._xy = asarray([self._pos[node] for node in self.nodes])
        self.xaxis_data = self._xy[:,0]
        self.yaxis_data = self._xy[:,1]

        # Initial draw
        self.default_props = {'nodesize' : 50,
                              'nodecolor' : 'blue',
                              'edge_color' : 'gray',
                              'edge_color_selected' : 'red'}
        self.node_collection = None
        self.edge_collection = None
        self.node_labels = None
        lw = zeros(self.xaxis_data.shape)
        self.node_collection = self.axes.scatter(self.xaxis_data, self.yaxis_data,
                                                 s=self._nodesize,
                                                 c=self._nodecolor,
                                                 linewidth=lw,
                                                 zorder=3)
        self._mappable = self.node_collection

        # selected nodes is a transparent graph that adjust node-edge visibility
        # according to the current selection needed to get get the selected
        # nodes 'on top' as zorder may not be defined individually
        self.selected_nodes = self.axes.scatter(self.xaxis_data,
                                                self.yaxis_data,
                                                s=self._nodesize,
                                                c=self._nodecolor,
                                                edgecolor='r',
                                                linewidth=lw,
                                                zorder=4,
                                                alpha=0)

        edge_color = self.default_props['edge_color']
        self.edge_collection = networkx.draw_networkx_edges(self.graph,
                                                            self._pos,
                                                            ax=self.axes,
                                                            edge_color=edge_color)
        # edge color rgba-arrays
        self._edge_color_rgba = matlib.repmat(plots.ColorConverter().to_rgba(edge_color),
                                       self.graph.number_of_edges(),1)
        self._edge_color_selected = plots.ColorConverter().to_rgba(self.default_props['edge_color_selected'])
        if self._with_labels:
            self.node_labels = networkx.draw_networkx_labels(self.graph,
                                                            self._pos,
                                                            ax=self.axes)
        
        # remove axes, frame and grid
        self.axes.set_xticks([])
        self.axes.set_yticks([])
        self.axes.grid(False)
        self.axes.set_frame_on(False)
        self.fig.subplots_adjust(left=0, right=1, bottom=0, top=1)

    def _add_ic_spin_buttons(self):
        """Adds spin buttons to the toolbar for selecting minimum and maximum
        threshold values on information content."""
        sb_min = gtk.SpinButton()
        sb_min.set_range(0, 100)
        sb_min.set_value(1)
        sb_min.set_increments(1, 3)
        sb_min.connect('value-changed', self._on_ic_value_changed)
        self._ic_sb_min = sb_min

        sb_max = gtk.SpinButton()
        sb_max.set_range(0, 100)
        sb_max.set_value(1)
        sb_max.set_increments(1, 3)
        sb_max.connect('value-changed', self._on_ic_value_changed)
        self._ic_sb_max = sb_max

        label = gtk.Label(" < IC < ")
        hbox = gtk.HBox()
        hbox.pack_start(sb_min)
        hbox.pack_start(label)
        hbox.pack_start(sb_max)
        ti = gtk.ToolItem()
        ti.set_expand(False)
        ti.add(hbox)
        sb_min.show()
        sb_max.show()
        label.show()
        hbox.show()
        ti.show()
        self._toolbar.insert(ti, -1)
        ti.set_tooltip(self._toolbar.tooltips, "Set information content threshold")
        
    def _calc_pos(self, graph):
        """Calculates position for graph nodes using 'dot' layout."""
        gv_graph = networkx.DiGraph()
        for start, end in graph.edges():
            gv_graph.add_edge(start.replace('GO:', ''), end.replace('GO:', ''))

        pos_gv = networkx.pygraphviz_layout(gv_graph, prog="dot")
        pos = {}
        for k, v in pos_gv.items():
            if k != "all":
                pos["GO:%s" % k] = v
            else:
                pos[k] = v
        return pos

    def set_ic_threshold(self, ic_min, ic_max):
        """Sets Information Content min and max to the given values.
        Updates the plot accordingly to show only values that have an
        information content within the boundaries. Other values are
        also excluded from being selected from the plot.
        @param ic_min Do not show nodes with IC below this value.
        @param ic_max Do not show nodes with IC above this value.
        """
        ic = getattr(main.workflow, 'current_ic', None)
        if ic == None:
            print "no ic set"
            return
        
        icnodes = ic.existing_identifiers('go-terms', self.nodes)
        icindices = ic.get_indices('go-terms', icnodes)
        a = ravel(ic.asarray()[icindices])
        ic_good = set(array(icnodes)[(a>ic_min) & (a<ic_max)])

        sizes = zeros(len(self.nodes))
        visible = set()
        for i, n in enumerate(self.nodes):
            if n in ic_good:
                sizes[i] = 50
                visible.add(n)
            else:
                sizes[i] = 0
        self.visible = visible
        
        self.node_collection._sizes = sizes
        self.canvas.draw()
        
    def _on_ic_value_changed(self, sb):
        """Callback on spin button value changes."""
        ic_min = self._ic_sb_min.get_value()
        ic_max = self._ic_sb_max.get_value()
        self.set_ic_threshold(ic_min, ic_max)
    
    def rectangle_select_callback(self, x1, y1, x2, y2, key):
        ydata = self.yaxis_data
        xdata = self.xaxis_data
        
        # find indices of selected area
        if x1>x2:
            x1, x2 = x2, x1
        if y1>y2:
            y1, y2 = y2, y1
        assert x1<=x2
        assert y1<=y2
        
        index = nonzero((xdata>x1) & (xdata<x2) & (ydata>y1) & (ydata<y2))[0]
        ids = self.visible.intersection([self.nodes[i] for i in index])
        ids = self.update_selection(ids, key)
        self.selection_listener(self.current_dim, ids)

    def lasso_select_callback(self, verts, key=None):
        xys = c_[self.xaxis_data[:,newaxis], self.yaxis_data[:,newaxis]]
        index = nonzero(points_inside_poly(xys, verts))[0]
        ids = [self.nodes[i] for i in index]
        ids = self.update_selection(ids, key)
        self.selection_listener(self.current_dim, ids)
        
    def set_current_selection(self, selection):
        linewidth = zeros(self.xaxis_data.shape)
        edge_color_rgba = self._edge_color_rgba.copy()
        index = [i for i in range(len(self.nodes)) if self.nodes[i] in selection[self.current_dim]]
        if len(index) > 0:
            linewidth[index] = 2
            idents = selection[self.current_dim]
            edge_index = [i for i,edge in enumerate(self.graph.edges()) if (edge[0] in idents and  edge[1] in idents)]
            if len(edge_index)>0:
                for i in edge_index:
                    edge_color_rgba[i,:] = self._edge_color_selected
                self._A = None
        
        self.edge_collection._colors = edge_color_rgba
        self.selected_nodes.set_linewidth(linewidth)
        self.canvas.draw()

    def is_mappable_with(self, obj):
        """Returns True if dataset/selection is mappable with this plot.
        """
        if isinstance(obj, fluents.dataset.Dataset):
            if self.current_dim in obj.get_dim_name():
                return True
        return False

    def _update_color_from_dataset(self, ds):
        """Updates the facecolors from a dataset.
        """

        array = ds.asarray()

        #only support for 2d-arrays:
        try:
            m, n = array.shape
        except:
            raise ValueError, "No support for more than 2 dimensions."
        # is dataset a vector or matrix?
        if not n==1:
            # we have a category dataset
            if isinstance(ds, fluents.dataset.CategoryDataset):
                vec = dot(array, diag(arange(n))).sum(1)
            else:
                vec = array.sum(1)
        else:
            vec = array.ravel()

        indices = ds.get_indices(self.current_dim, self.nodes)
        nodes = ds.existing_identifiers(self.current_dim, self.nodes)

        v = vec.take(indices, 0)
        vec_min = min(vec[vec > -inf])
        vec_max = max(vec[vec < inf])
        v[v==inf] = vec_max
        v[v==-inf] = vec_min

        d = dict(zip(nodes, list(v))) 

        map_vec = zeros(len(self.nodes))
        for i, n in enumerate(self.nodes):
            map_vec[i] = d.get(n, -1)

        # update facecolors
        self.node_collection.set_array(map_vec)
        self.node_collection.set_clim(vec_min, vec_max)
        self.node_collection.update_scalarmappable() #sets facecolors from array
        self.canvas.draw()