def breadth_first_search(A, start):
"""
Breadth-First-Search (BFS) of a graph in CSR or CSC matrix format starting
from a given node (row). Takes Qobjs and CSR or CSC matrices as inputs.
This function requires a matrix with symmetric structure.
Use A+trans(A) if original matrix is not symmetric or not sure.
Parameters
----------
A : csc_matrix, csr_matrix
Input graph in CSC or CSR matrix format
start : int
Staring node for BFS traversal.
Returns
-------
order : array
Order in which nodes are traversed from starting node.
levels : array
Level of the nodes in the order that they are traversed.
"""
if not (sp.isspmatrix_csc(A) or sp.isspmatrix_csr(A)):
raise TypeError('Input must be CSC or CSR sparse matrix.')
num_rows = A.shape[0]
start = int(start)
order, levels = _breadth_first_search(A.indices, A.indptr, num_rows, start)
# since maybe not all nodes are in search, check for unused entires in
# arrays
return order[order != -1], levels[levels != -1]
def breadth_first_search(A, start):
"""
Breadth-First-Search (BFS) of a graph in CSR or CSC matrix format starting
from a given node (row). Takes Qobjs and CSR or CSC matrices as inputs.
This function requires a matrix with symmetric structure.
Use A+trans(A) if original matrix is not symmetric or not sure.
Parameters
----------
A : qobj, csr_matrix
Input graph in CSR matrix form
start : int
Staring node for BFS traversal.
Returns
-------
order : array
Order in which nodes are traversed from starting node.
levels : array
Level of the nodes in the order that they are traversed.
"""
if A.__class__.__name__ == 'Qobj':
A = A.data
num_rows = A.shape[0]
start = int(start)
order, levels = _breadth_first_search(A.indices, A.indptr, num_rows, start)
#since maybe not all nodes are in search, check for unused entires in arrays
return order[order != -1], levels[levels != -1]
def breadth_first_search(A, start):
"""
Breadth-First-Search (BFS) of a graph in CSR or CSC matrix format starting
from a given node (row). Takes Qobjs and CSR or CSC matrices as inputs.
This function requires a matrix with symmetric structure.
Use A+trans(A) if original matrix is not symmetric or not sure.
Parameters
----------
A : csc_matrix, csr_matrix
Input graph in CSC or CSR matrix format
start : int
Staring node for BFS traversal.
Returns
-------
order : array
Order in which nodes are traversed from starting node.
levels : array
Level of the nodes in the order that they are traversed.
"""
if not (sp.isspmatrix_csc(A) or sp.isspmatrix_csr(A)):
raise TypeError('Input must be CSC or CSR sparse matrix.')
num_rows = A.shape[0]
start = int(start)
order, levels = _breadth_first_search(A.indices, A.indptr, num_rows, start)
# since maybe not all nodes are in search, check for unused entires in
# arrays
return order[order != -1], levels[levels != -1]
def breadth_first_search(A,start):
"""
Breadth-First-Search (BFS) of a graph in CSR or CSC matrix format starting
from a given node (row). Takes Qobjs and CSR or CSC matrices as inputs.
This function requires a matrix with symmetric structure.
Use A+trans(A) if original matrix is not symmetric or not sure.
Parameters
----------
A : qobj, csr_matrix
Input graph in CSR matrix form
start : int
Staring node for BFS traversal.
Returns
-------
order : array
Order in which nodes are traversed from starting node.
levels : array
Level of the nodes in the order that they are traversed.
"""
if A.__class__.__name__=='Qobj':
A=A.data
num_rows=A.shape[0]
start=int(start)
order, levels = _breadth_first_search(A.indices,A.indptr, num_rows, start)
#since maybe not all nodes are in search, check for unused entires in arrays
return order[order!=-1], levels[levels!=-1]
