Name

adj2sp — converts adjacency form into sparse matrix.

Parameters

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

mn

row vector with 2 entries, mn=size(A) (optional).

A

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

Description

 
sp2adj converts an adjacency form representation of a matrix
into its standard Scilab representation (utility fonction).
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

sp2adj, spcompack