I'm trying to create a graph with graph-tool (https://graph-tool.skewed.de) from csv file that content like:
A,B,50
A,C,34
C,D,55
D,D,80
A,D,90
B,D,78
Now I want to create a graph with A, B, C, D as nodes and the third column numbers as edges. I am using graph-tool library. The third column number shows the common items shared by A,B and A,C and so on.
I can do it by "networkx" (read_edgelist and etc) but I want to do it with graph-tool.
You can use add_edge_list() to add a list of edges. If them are stored with names that differ from the index assigned automatically it will return a list of string containing the names from the list.
EXAMPLE:
from graph_tool.all import *
import csv
g=Graph(directed=False)
csv_E = csv.reader(open('*text_input*'))
e_weight=g.new_edge_property('float')
v_names=g.add_edge_list(csv_E,hashed=True,string_vals=True,eprops=[e_weight])
#this will assign the weight to the propery map *e_weight* and the names to *v_names*
graph_draw(g, vertex_text=v_names)
Assuming you already know how to read the CSV file in Python (for example, using the CSV library), The docs on the website explain how to do this very clearly.
Something like
import graph_tool
g = Graph(directed=False)
# this is the result of csv.parse(file)
list_of_edges = [['A', 'B', 50], ['A','C',34], ['C','D',55], ['D','D',80], ['A','D',90], ['B','D',78]]
vertices = {}
for e in list_of_edges:
if e[0] not in vertices:
vertices[e[0]] = True
if e[1] not in vertices:
vertices[e[1]] = True
for d in vertices:
vertices[d] = g.add_vertex()
for edge in list_of_edges:
g.add_edge(vertices[edge[0]], vertices[edge[1]])
[[A , B, 50], [A, C, 50]]in memory?