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Create adjacency matrix from edge list

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1

Hello i'm trying to code the generation of an adjacency matrix from an edge list but i can't get my code to work and i don't understand why

i've tried inversing the indexes and running it step by step

graph1=[[0,2,3,4],[1,2,4],[0,2,3,4],[1,2,3,4],[0,2,4]]

def Adjacency(graph):
 index = 0 #Index of the sublist
 matrix = [[0]*len(graph)]*len(graph)
 print(matrix) 
 for sublist in graph:
 for value in sublist:
 print(value)
 matrice[index][value] = 1
 index+=1

 print(matrix)

Adjacence(graphe1) 

the expected output should be

[[1 0 1 1 1]
 [0 1 1 0 1]
 [1 0 1 1 1]
 [0 1 1 1 1]
 [1 0 1 0 1]] 

but instead i got

[[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1]]

i'm pratically sure that i forgot a small detail but i can't figure it out.
i'd be glad if somebody could me.

python graph

share|improve this question

asked Mar 28 at 14:15

SliteSlite

3911 silver badge99 bronze badges

add a comment
 | 

1

Hello i'm trying to code the generation of an adjacency matrix from an edge list but i can't get my code to work and i don't understand why

i've tried inversing the indexes and running it step by step

graph1=[[0,2,3,4],[1,2,4],[0,2,3,4],[1,2,3,4],[0,2,4]]

def Adjacency(graph):
 index = 0 #Index of the sublist
 matrix = [[0]*len(graph)]*len(graph)
 print(matrix) 
 for sublist in graph:
 for value in sublist:
 print(value)
 matrice[index][value] = 1
 index+=1

 print(matrix)

Adjacence(graphe1) 

the expected output should be

[[1 0 1 1 1]
 [0 1 1 0 1]
 [1 0 1 1 1]
 [0 1 1 1 1]
 [1 0 1 0 1]] 

but instead i got

[[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1]]

i'm pratically sure that i forgot a small detail but i can't figure it out.
i'd be glad if somebody could me.

python graph

share|improve this question

asked Mar 28 at 14:15

SliteSlite

3911 silver badge99 bronze badges

add a comment
 | 

Hello i'm trying to code the generation of an adjacency matrix from an edge list but i can't get my code to work and i don't understand why

i've tried inversing the indexes and running it step by step

graph1=[[0,2,3,4],[1,2,4],[0,2,3,4],[1,2,3,4],[0,2,4]]

def Adjacency(graph):
 index = 0 #Index of the sublist
 matrix = [[0]*len(graph)]*len(graph)
 print(matrix) 
 for sublist in graph:
 for value in sublist:
 print(value)
 matrice[index][value] = 1
 index+=1

 print(matrix)

Adjacence(graphe1) 

the expected output should be

[[1 0 1 1 1]
 [0 1 1 0 1]
 [1 0 1 1 1]
 [0 1 1 1 1]
 [1 0 1 0 1]] 

but instead i got

[[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1]]

i'm pratically sure that i forgot a small detail but i can't figure it out.
i'd be glad if somebody could me.

python graph

share|improve this question

asked Mar 28 at 14:15

SliteSlite

3911 silver badge99 bronze badges

graph1=[[0,2,3,4],[1,2,4],[0,2,3,4],[1,2,3,4],[0,2,4]]

def Adjacency(graph):
 index = 0 #Index of the sublist
 matrix = [[0]*len(graph)]*len(graph)
 print(matrix) 
 for sublist in graph:
 for value in sublist:
 print(value)
 matrice[index][value] = 1
 index+=1

 print(matrix)

Adjacence(graphe1) 

[[1 0 1 1 1]
 [0 1 1 0 1]
 [1 0 1 1 1]
 [0 1 1 1 1]
 [1 0 1 0 1]] 

[[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1], 
[1, 1, 1, 1, 1]]

share|improve this question

asked Mar 28 at 14:15

SliteSlite

3911 silver badge99 bronze badges

share|improve this question

asked Mar 28 at 14:15

SliteSlite

3911 silver badge99 bronze badges

asked Mar 28 at 14:15

SliteSlite

3911 silver badge99 bronze badges

asked Mar 28 at 14:15

SliteSlite

3911 silver badge99 bronze badges

1 Answer
1

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2

you need to change the line:

matrix = [[0]*len(graph)]*len(graph)

to:

matrix = [[0]*len(graph) for i in range(len(graph))]

This is becasue when you make an array the way you did it stores them differently and they can edit multiple values at once. Try reading this question or this one

share|improve this answer

answered Mar 28 at 14:25

BuzzBuzz

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add a comment
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2

you need to change the line:

matrix = [[0]*len(graph)]*len(graph)

to:

matrix = [[0]*len(graph) for i in range(len(graph))]

This is becasue when you make an array the way you did it stores them differently and they can edit multiple values at once. Try reading this question or this one

share|improve this answer

answered Mar 28 at 14:25

BuzzBuzz

1,5721818 silver badges2424 bronze badges

add a comment
 | 

2

you need to change the line:

matrix = [[0]*len(graph)]*len(graph)

to:

matrix = [[0]*len(graph) for i in range(len(graph))]

This is becasue when you make an array the way you did it stores them differently and they can edit multiple values at once. Try reading this question or this one

share|improve this answer

answered Mar 28 at 14:25

BuzzBuzz

1,5721818 silver badges2424 bronze badges

add a comment
 | 

you need to change the line:

matrix = [[0]*len(graph)]*len(graph)

to:

matrix = [[0]*len(graph) for i in range(len(graph))]

This is becasue when you make an array the way you did it stores them differently and they can edit multiple values at once. Try reading this question or this one

share|improve this answer

answered Mar 28 at 14:25

BuzzBuzz

1,5721818 silver badges2424 bronze badges

matrix = [[0]*len(graph)]*len(graph)

matrix = [[0]*len(graph) for i in range(len(graph))]

share|improve this answer

answered Mar 28 at 14:25

BuzzBuzz

1,5721818 silver badges2424 bronze badges

answered Mar 28 at 14:25

BuzzBuzz

1,5721818 silver badges2424 bronze badges

answered Mar 28 at 14:25

BuzzBuzz

1,5721818 silver badges2424 bronze badges