'Update the printed contents of the node for regression trees'

def update_node_info_reg(self, node):

    node_inst = node.node_inst
    (mean, var) = self.tree_adapter.get_distribution(node_inst)[0]
    insts = self.tree_adapter.num_samples(node_inst)
    text = '{:.1f}    \xc2\xb1    {:.1f}<br/>'.format(mean, var)
    text += '{}    instances'.format(insts)
    text = self._update_node_info_attr_name(node, text)
    node.setHtml('<p    style="line-height:    120%;    margin-bottom:    0">{}</p>'.format(text))
