Name

sp2adj — converts sparse matrix into adjacency form

Parameters

A

real or complex sparse matrix (nz non-zero entries)

xadj

integer vector of length (n+1).

adjncy

integer vector of length nz containing the row indices for the corresponding elements in anz

anz

column vector of length nz, containing the non-zero elements of A

Description

 
sp2adj converts a sparse matrix into its adjacency form (utility fonction).
A =  n x m sparse matrix. xadj, adjncy, anz = adjacency representation of A i.e:

xadj(j+1)-xadj(j) = number of non zero entries in row j. adjncy = column index of the non zeros entries in row 1, row 2,..., row n. anz = values of non zero entries in row 1, row 2,..., row n. xadj is a (column) vector of size n+1 and adjncy is an integer (column) vector of size nz=nnz(A). anz is a real vector of size nz=nnz(A).

Examples

 
A = sprand(100,50,.05);
[xadj,adjncy,anz]= sp2adj(A);
[n,m]=size(A);
p = adj2sp(xadj,adjncy,anz,[n,m]);
A-p

See Also

adj2sp, sparse, spcompack, spget