Problem with add_edge_list(eprop=x)

graph-tool
1

I'd like to use the "add_edge_list" function to add edges to my graph, and
simultaneously assign a value for an edge property map for each of the added
edges.

When I try the following example (with no edge property map information)
works fine:

elist1 = np.array([[0,1], [1, 2]]) #edge list with no value for edge
property map data (only the source and target for the edges)
g = gt.Graph()
my_eprop = g.new_edge_property('bool')
g.add_edge_list(elist)

But with the following example, I get the error below:

elist2 = np.array([[0,1, 1], [1, 2, 0]]) #edge list with edge property map
value in 3rd column
g = gt.Graph()
my_eprop = g.new_edge_property('bool')
g.add_edge_list(elist2, eprops=my_eprop)

Error:

2

The 'eprops' parameter expects a list. The last line should have been:

  g.add_edge_list(elist2, eprops=[my_eprop])

Best,
Tiago

3

Thanks!

attachment.html (1.42 KB)

4

Sir,

How to add multiple edge properties?
If my_eprop and other_eprop are two arrays of edge properties and there is
another column of values in elist2, then

g.add_edge_list(elist2,eprops=[my_eprop,other_eprop])

Is this correct or not?

This doesn't give any error but it takes only the second property column
from elist2 while ignores the first one.

5

If you want us to understand the problem you are having, you must provide a
minimal and self-contained example that shows it, otherwise there is little
we can do.

Best,
Tiago

6

I have a data frame where I have five columns. First two columns are the
source and sink nodes of interaction while the other three columns are three
kinds of edge properties.

*import pandas as pd
import graph_tool as gt

df = pd.DataFrame({'S':['a','b','c'], 'D':['b','c','a'],
'w1':[0.2,0.5,0.6], 'w2':[0.4,0.55,0.99], 'w3':[1,3,5]})

g = gt.Graph()

eprop1 = g.new_edge_property('float')
eprop2 = g.new_edge_property('float')
eprop3 = g.new_edge_property('int')*

Now if I want to add this to the properties to my network then

*g.edge_properties['eprop1'] = eprop1
g.edge_properties['eprop2'] = eprop2
g.edge_properties['eprop3'] = eprop3

7

This works perfectly for me. In fact, the version with eprops=[eprop1] does
not work, as the number of columns is unmatched.

What version of graph-tool are you using?

Best,
Tiago

8

Its' working when I changed the edge property type 'int' to 'float' for the
last one.

Also, the assigned property values are reversed in order when I tried the
same for another example with only two property maps.

So for now, the problem seems to have solved.

Graph Tool version is 2.27

9

Its' working when I changed the edge property type 'int' to 'float' for the
last one.

I can't reproduce this. The example you gave works as expected, regardless
of the property type.

Note that so far you have not produced a minimal example that even allegedly
reproduces the problem you are encountering. For some reason you gave us an
example that _works_ instead of one that doesn't. Could you please provide a
complete and minimal example that _shows_ the problem, i.e. gives the wrong
output?

Also, the assigned property values are reversed in order when I tried the
same for another example with only two property maps.

I can't reproduce this either. And as already explained many times, it is
useless to mention problems without a reproducible example.

So for now, the problem seems to have solved.

???

If the problems you mention are really there, then they need to be fixed. I
ask of you to please produce a minimal and complete example for them.

Best,
Tiago

10

*import graph_tool as gt

netCoex = gt.Graph() *#create a network