odoo/openerp/tools/graph.py

777 lines
26 KiB
Python
Executable File

#!/usr/bin/env python
# -*- coding: utf-8 -*-
##############################################################################
#
# OpenERP, Open Source Management Solution
# Copyright (C) 2004-2009 Tiny SPRL (<http://tiny.be>).
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
##############################################################################
import operator
import math
class graph(object):
def __init__(self, nodes, transitions, no_ancester=None):
"""Initialize graph's object
@param nodes list of ids of nodes in the graph
@param transitions list of edges in the graph in the form (source_node, destination_node)
@param no_ancester list of nodes with no incoming edges
"""
self.nodes = nodes or []
self.edges = transitions or []
self.no_ancester = no_ancester or {}
trans = {}
for t in transitions:
trans.setdefault(t[0], [])
trans[t[0]].append(t[1])
self.transitions = trans
self.result = {}
def init_rank(self):
"""Computes rank of the nodes of the graph by finding initial feasible tree
"""
self.edge_wt = {}
for link in self.links:
self.edge_wt[link] = self.result[link[1]]['x'] - self.result[link[0]]['x']
tot_node = len(self.partial_order)
#do until all the nodes in the component are searched
while self.tight_tree()<tot_node:
list_node = []
list_edge = []
for node in self.nodes:
if node not in self.reachable_nodes:
list_node.append(node)
for edge in self.edge_wt:
if edge not in self.tree_edges:
list_edge.append(edge)
slack = 100
for edge in list_edge:
if ((edge[0] in self.reachable_nodes and edge[1] not in self.reachable_nodes) or
(edge[1] in self.reachable_nodes and edge[0] not in self.reachable_nodes)):
if slack > self.edge_wt[edge]-1:
slack = self.edge_wt[edge]-1
new_edge = edge
if new_edge[0] not in self.reachable_nodes:
delta = -(self.edge_wt[new_edge]-1)
else:
delta = self.edge_wt[new_edge]-1
for node in self.result:
if node in self.reachable_nodes:
self.result[node]['x'] += delta
for edge in self.edge_wt:
self.edge_wt[edge] = self.result[edge[1]]['x'] - self.result[edge[0]]['x']
self.init_cutvalues()
def tight_tree(self):
self.reachable_nodes = []
self.tree_edges = []
self.reachable_node(self.start)
return len(self.reachable_nodes)
def reachable_node(self, node):
"""Find the nodes of the graph which are only 1 rank apart from each other
"""
if node not in self.reachable_nodes:
self.reachable_nodes.append(node)
for edge in self.edge_wt:
if edge[0]==node:
if self.edge_wt[edge]==1:
self.tree_edges.append(edge)
if edge[1] not in self.reachable_nodes:
self.reachable_nodes.append(edge[1])
self.reachable_node(edge[1])
def init_cutvalues(self):
"""Initailize cut values of edges of the feasible tree.
Edges with negative cut-values are removed from the tree to optimize rank assignment
"""
self.cut_edges = {}
self.head_nodes = []
i=0
for edge in self.tree_edges:
self.head_nodes = []
rest_edges = []
rest_edges += self.tree_edges
del rest_edges[i]
self.head_component(self.start, rest_edges)
i+=1
positive = 0
negative = 0
for source_node in self.transitions:
if source_node in self.head_nodes:
for dest_node in self.transitions[source_node]:
if dest_node not in self.head_nodes:
negative+=1
else:
for dest_node in self.transitions[source_node]:
if dest_node in self.head_nodes:
positive+=1
self.cut_edges[edge] = positive - negative
def head_component(self, node, rest_edges):
"""Find nodes which are reachable from the starting node, after removing an edge
"""
if node not in self.head_nodes:
self.head_nodes.append(node)
for edge in rest_edges:
if edge[0]==node:
self.head_component(edge[1],rest_edges)
def process_ranking(self, node, level=0):
"""Computes initial feasible ranking after making graph acyclic with depth-first search
"""
if node not in self.result:
self.result[node] = {'y': None, 'x':level, 'mark':0}
else:
if level > self.result[node]['x']:
self.result[node]['x'] = level
if self.result[node]['mark']==0:
self.result[node]['mark'] = 1
for sec_end in self.transitions.get(node, []):
self.process_ranking(sec_end, level+1)
def make_acyclic(self, parent, node, level, tree):
"""Computes Partial-order of the nodes with depth-first search
"""
if node not in self.partial_order:
self.partial_order[node] = {'level':level, 'mark':0}
if parent:
tree.append((parent, node))
if self.partial_order[node]['mark']==0:
self.partial_order[node]['mark'] = 1
for sec_end in self.transitions.get(node, []):
self.links.append((node, sec_end))
self.make_acyclic(node, sec_end, level+1, tree)
return tree
def rev_edges(self, tree):
"""reverse the direction of the edges whose source-node-partail_order> destination-node-partail_order
to make the graph acyclic
"""
Is_Cyclic = False
i=0
for link in self.links:
src = link[0]
des = link[1]
edge_len = self.partial_order[des]['level'] - self.partial_order[src]['level']
if edge_len < 0:
del self.links[i]
self.links.insert(i, (des, src))
self.transitions[src].remove(des)
self.transitions.setdefault(des, []).append(src)
Is_Cyclic = True
elif math.fabs(edge_len) > 1:
Is_Cyclic = True
i += 1
return Is_Cyclic
def exchange(self, e, f):
"""Exchange edges to make feasible-tree optimized
:param e: edge with negative cut-value
:param f: new edge with minimum slack-value
"""
del self.tree_edges[self.tree_edges.index(e)]
self.tree_edges.append(f)
self.init_cutvalues()
def enter_edge(self, edge):
"""Finds a new_edge with minimum slack value to replace an edge with negative cut-value
@param edge edge with negative cut-value
"""
self.head_nodes = []
rest_edges = []
rest_edges += self.tree_edges
del rest_edges[rest_edges.index(edge)]
self.head_component(self.start, rest_edges)
if edge[1] in self.head_nodes:
l = []
for node in self.result:
if node not in self.head_nodes:
l.append(node)
self.head_nodes = l
slack = 100
new_edge = edge
for source_node in self.transitions:
if source_node in self.head_nodes:
for dest_node in self.transitions[source_node]:
if dest_node not in self.head_nodes:
if slack>(self.edge_wt[edge]-1):
slack = self.edge_wt[edge]-1
new_edge = (source_node, dest_node)
return new_edge
def leave_edge(self):
"""Returns the edge with negative cut_value(if exists)
"""
if self.critical_edges:
for edge in self.critical_edges:
self.cut_edges[edge] = 0
for edge in self.cut_edges:
if self.cut_edges[edge]<0:
return edge
return None
def finalize_rank(self, node, level):
self.result[node]['x'] = level
for destination in self.optimal_edges.get(node, []):
self.finalize_rank(destination, level+1)
def normalize(self):
"""The ranks are normalized by setting the least rank to zero.
"""
least_rank = min(map(lambda x: x['x'], self.result.values()))
if least_rank!=0:
for node in self.result:
self.result[node]['x']-=least_rank
def make_chain(self):
"""Edges between nodes more than one rank apart are replaced by chains of unit
length edges between temporary nodes.
"""
for edge in self.edge_wt:
if self.edge_wt[edge]>1:
self.transitions[edge[0]].remove(edge[1])
start = self.result[edge[0]]['x']
end = self.result[edge[1]]['x']
for rank in range(start+1, end):
if not self.result.get((rank, 'temp'), False):
self.result[(rank, 'temp')] = {'y': None, 'x': rank, 'mark': 0}
for rank in range(start, end):
if start==rank:
self.transitions[edge[0]].append((rank+1, 'temp'))
elif rank==end-1:
self.transitions.setdefault((rank, 'temp'), []).append(edge[1])
else:
self.transitions.setdefault((rank, 'temp'), []).append((rank+1, 'temp'))
def init_order(self, node, level):
"""Initialize orders the nodes in each rank with depth-first search
"""
if not self.result[node]['y']:
self.result[node]['y'] = self.order[level]
self.order[level] += 1
for sec_end in self.transitions.get(node, []):
if node!=sec_end:
self.init_order(sec_end, self.result[sec_end]['x'])
def order_heuristic(self):
for i in range(12):
self.wmedian()
def wmedian(self):
"""Applies median heuristic to find optimzed order of the nodes with in their ranks
"""
for level in self.levels:
node_median = []
nodes = self.levels[level]
for node in nodes:
node_median.append((node, self.median_value(node, level-1)))
sort_list = sorted(node_median, key=operator.itemgetter(1))
new_list = [tuple[0] for tuple in sort_list]
self.levels[level] = new_list
order = 0
for node in nodes:
self.result[node]['y'] = order
order +=1
def median_value(self, node, adj_rank):
"""Returns median value of a vertex , defined as the median position of the adjacent vertices
@param node node to process
@param adj_rank rank 1 less than the node's rank
"""
adj_nodes = self.adj_position(node, adj_rank)
l = len(adj_nodes)
m = l/2
if l==0:
return -1.0
elif l%2 == 1:
return adj_nodes[m]#median of the middle element
elif l==2:
return (adj_nodes[0]+adj_nodes[1])/2
else:
left = adj_nodes[m-1] - adj_nodes[0]
right = adj_nodes[l-1] - adj_nodes[m]
return ((adj_nodes[m-1]*right) + (adj_nodes[m]*left))/(left+right)
def adj_position(self, node, adj_rank):
"""Returns list of the present positions of the nodes adjacent to node in the given adjacent rank.
@param node node to process
@param adj_rank rank 1 less than the node's rank
"""
pre_level_nodes = self.levels.get(adj_rank, [])
adj_nodes = []
if pre_level_nodes:
for src in pre_level_nodes:
if self.transitions.get(src) and node in self.transitions[src]:
adj_nodes.append(self.result[src]['y'])
return adj_nodes
def preprocess_order(self):
levels = {}
for r in self.partial_order:
l = self.result[r]['x']
levels.setdefault(l,[])
levels[l].append(r)
self.levels = levels
def graph_order(self):
"""Finds actual-order of the nodes with respect to maximum number of nodes in a rank in component
"""
mid_pos = 0.0
max_level = max(map(lambda x: len(x), self.levels.values()))
for level in self.levels:
if level:
no = len(self.levels[level])
factor = (max_level - no) * 0.10
list = self.levels[level]
list.reverse()
if no%2==0:
first_half = list[no/2:]
factor = -factor
else:
first_half = list[no/2+1:]
if max_level==1:#for the case when horizontal graph is there
self.result[list[no/2]]['y'] = mid_pos + (self.result[list[no/2]]['x']%2 * 0.5)
else:
self.result[list[no/2]]['y'] = mid_pos + factor
last_half = list[:no/2]
i=1
for node in first_half:
self.result[node]['y'] = mid_pos - (i + factor)
i += 1
i=1
for node in last_half:
self.result[node]['y'] = mid_pos + (i + factor)
i += 1
else:
self.max_order += max_level+1
mid_pos = self.result[self.start]['y']
def tree_order(self, node, last=0):
mid_pos = self.result[node]['y']
l = self.transitions.get(node, [])
l.reverse()
no = len(l)
rest = no%2
first_half = l[no/2+rest:]
last_half = l[:no/2]
for i, child in enumerate(first_half):
self.result[child]['y'] = mid_pos - (i+1 - (0 if rest else 0.5))
if self.transitions.get(child, False):
if last:
self.result[child]['y'] = last + len(self.transitions[child])/2 + 1
last = self.tree_order(child, last)
if rest:
mid_node = l[no/2]
self.result[mid_node]['y'] = mid_pos
if self.transitions.get(mid_node, False):
if last:
self.result[mid_node]['y'] = last + len(self.transitions[mid_node])/2 + 1
if node!=mid_node:
last = self.tree_order(mid_node)
else:
if last:
self.result[mid_node]['y'] = last + 1
self.result[node]['y'] = self.result[mid_node]['y']
mid_pos = self.result[node]['y']
i=1
last_child = None
for child in last_half:
self.result[child]['y'] = mid_pos + (i - (0 if rest else 0.5))
last_child = child
i += 1
if self.transitions.get(child, False):
if last:
self.result[child]['y'] = last + len(self.transitions[child])/2 + 1
if node!=child:
last = self.tree_order(child, last)
if last_child:
last = self.result[last_child]['y']
return last
def process_order(self):
"""Finds actual-order of the nodes with respect to maximum number of nodes in a rank in component
"""
if self.Is_Cyclic:
max_level = max(map(lambda x: len(x), self.levels.values()))
if max_level%2:
self.result[self.start]['y'] = (max_level+1)/2 + self.max_order + (self.max_order and 1)
else:
self.result[self.start]['y'] = max_level /2 + self.max_order + (self.max_order and 1)
self.graph_order()
else:
self.result[self.start]['y'] = 0
self.tree_order(self.start, 0)
min_order = math.fabs(min(map(lambda x: x['y'], self.result.values())))
index = self.start_nodes.index(self.start)
same = False
roots = []
if index>0:
for start in self.start_nodes[:index]:
same = True
for edge in self.tree_list[start][1:]:
if edge in self.tree_list[self.start]:
continue
else:
same = False
break
if same:
roots.append(start)
if roots:
min_order += self.max_order
else:
min_order += self.max_order + 1
for level in self.levels:
for node in self.levels[level]:
self.result[node]['y'] += min_order
if roots:
roots.append(self.start)
one_level_el = self.tree_list[self.start][0][1]
base = self.result[one_level_el]['y']# * 2 / (index + 2)
no = len(roots)
first_half = roots[:no/2]
if no%2==0:
last_half = roots[no/2:]
else:
last_half = roots[no/2+1:]
factor = -math.floor(no/2)
for start in first_half:
self.result[start]['y'] = base + factor
factor += 1
if no%2:
self.result[roots[no/2]]['y'] = base + factor
factor +=1
for start in last_half:
self.result[start]['y'] = base + factor
factor += 1
self.max_order = max(map(lambda x: x['y'], self.result.values()))
def find_starts(self):
"""Finds other start nodes of the graph in the case when graph is disconneted
"""
rem_nodes = []
for node in self.nodes:
if not self.partial_order.get(node):
rem_nodes.append(node)
cnt = 0
while True:
if len(rem_nodes)==1:
self.start_nodes.append(rem_nodes[0])
break
else:
count = 0
new_start = rem_nodes[0]
largest_tree = []
for node in rem_nodes:
self.partial_order = {}
tree = self.make_acyclic(None, node, 0, [])
if len(tree)+1 > count:
count = len(tree) + 1
new_start = node
largest_tree = tree
else:
if not largest_tree:
new_start = rem_nodes[0]
rem_nodes.remove(new_start)
self.start_nodes.append(new_start)
for edge in largest_tree:
if edge[0] in rem_nodes:
rem_nodes.remove(edge[0])
if edge[1] in rem_nodes:
rem_nodes.remove(edge[1])
if not rem_nodes:
break
def rank(self):
"""Finds the optimized rank of the nodes using Network-simplex algorithm
"""
self.levels = {}
self.critical_edges = []
self.partial_order = {}
self.links = []
self.Is_Cyclic = False
self.tree_list[self.start] = self.make_acyclic(None, self.start, 0, [])
self.Is_Cyclic = self.rev_edges(self.tree_list[self.start])
self.process_ranking(self.start)
self.init_rank()
#make cut values of all tree edges to 0 to optimize feasible tree
e = self.leave_edge()
while e :
f = self.enter_edge(e)
if e==f:
self.critical_edges.append(e)
else:
self.exchange(e,f)
e = self.leave_edge()
#finalize rank using optimum feasible tree
# self.optimal_edges = {}
# for edge in self.tree_edges:
# source = self.optimal_edges.setdefault(edge[0], [])
# source.append(edge[1])
# self.finalize_rank(self.start, 0)
#normalization
self.normalize()
for edge in self.edge_wt:
self.edge_wt[edge] = self.result[edge[1]]['x'] - self.result[edge[0]]['x']
def order_in_rank(self):
"""Finds optimized order of the nodes within their ranks using median heuristic
"""
self.make_chain()
self.preprocess_order()
self.order = {}
max_rank = max(map(lambda x: x, self.levels.keys()))
for i in range(max_rank+1):
self.order[i] = 0
self.init_order(self.start, self.result[self.start]['x'])
for level in self.levels:
self.levels[level].sort(lambda x, y: cmp(self.result[x]['y'], self.result[y]['y']))
self.order_heuristic()
self.process_order()
def process(self, starting_node):
"""Process the graph to find ranks and order of the nodes
@param starting_node node from where to start the graph search
"""
self.start_nodes = starting_node or []
self.partial_order = {}
self.links = []
self.tree_list = {}
if self.nodes:
if self.start_nodes:
#add dummy edges to the nodes which does not have any incoming edges
tree = self.make_acyclic(None, self.start_nodes[0], 0, [])
for node in self.no_ancester:
for sec_node in self.transitions.get(node, []):
if sec_node in self.partial_order.keys():
self.transitions[self.start_nodes[0]].append(node)
break
self.partial_order = {}
tree = self.make_acyclic(None, self.start_nodes[0], 0, [])
# if graph is disconnected or no start-node is given
#than to find starting_node for each component of the node
if len(self.nodes) > len(self.partial_order):
self.find_starts()
self.max_order = 0
#for each component of the graph find ranks and order of the nodes
for s in self.start_nodes:
self.start = s
self.rank() # First step:Netwoek simplex algorithm
self.order_in_rank() #Second step: ordering nodes within ranks
def __str__(self):
result = ''
for l in self.levels:
result += 'PosY: ' + str(l) + '\n'
for node in self.levels[l]:
result += '\tPosX: '+ str(self.result[node]['y']) + ' - Node:' + str(node) + "\n"
return result
def scale(self, maxx, maxy, nwidth=0, nheight=0, margin=20):
"""Computes actual co-ordiantes of the nodes
"""
#for flat edges ie. source an destination nodes are on the same rank
for src in self.transitions:
for des in self.transitions[src]:
if self.result[des]['x'] - self.result[src]['x'] == 0:
self.result[src]['x'] += 0.08
self.result[des]['x'] -= 0.08
factorX = maxx + nheight
factorY = maxy + nwidth
for node in self.result:
self.result[node]['y'] = (self.result[node]['y']) * factorX + margin
self.result[node]['x'] = (self.result[node]['x']) * factorY + margin
def result_get(self):
return self.result
if __name__=='__main__':
starting_node = ['profile'] # put here nodes with flow_start=True
nodes = ['project','account','hr','base','product','mrp','test','profile']
transitions = [
('profile','mrp'),
('mrp','project'),
('project','product'),
('mrp','hr'),
('mrp','test'),
('project','account'),
('project','hr'),
('product','base'),
('account','product'),
('account','test'),
('account','base'),
('hr','base'),
('test','base')
]
radius = 20
g = graph(nodes, transitions)
g.process(starting_node)
g.scale(radius*3,radius*3, radius, radius)
from PIL import Image
from PIL import ImageDraw
img = Image.new("RGB", (800, 600), "#ffffff")
draw = ImageDraw.Draw(img)
result = g.result_get()
node_res = {}
for node in nodes:
node_res[node] = result[node]
for name,node in node_res.items():
draw.arc( (int(node['y']-radius), int(node['x']-radius),int(node['y']+radius), int(node['x']+radius) ), 0, 360, (128,128,128))
draw.text( (int(node['y']), int(node['x'])), str(name), (128,128,128))
for t in transitions:
draw.line( (int(node_res[t[0]]['y']), int(node_res[t[0]]['x']),int(node_res[t[1]]['y']),int(node_res[t[1]]['x'])),(128,128,128) )
img.save("graph.png", "PNG")
# vim:expandtab:smartindent:tabstop=4:softtabstop=4:shiftwidth=4: