Sparse Matrix as field in a Chapel object - sparse-matrix

Question

Following up on this question I now have a class Graph that includes a sparse matrix. Defined like
class Graph {
var vdom: domain(2),
SD: sparse subdomain(vdom),
A: [SD] real;
proc init(A: []) {
this.vdom = {A.domain.dim(1), A.domain.dim(2)};
for ij in A.domain {
this.SD += ij;
}
}
producing the error
chingon-base-test.chpl:30: error: halt reached - Sparse domain/array index out of bounds: (1, 2) (expected to be within {1..0, 1..0}
It appears SD is not getting redefined. What is the correct pattern? In the previous post, we talked about dense arrays, this is for sparse.
I am calling it via
var nv: int = 8,
D: domain(2) = {1..nv, 1..nv},
SD: sparse subdomain(D),
A: [SD] real;
SD += (1,2); A[1,2] = 1;
SD += (1,3); A[1,3] = 1;
SD += (1,4); A[1,4] = 1;
SD += (2,4); A[2,4] = 1;
SD += (3,4); A[3,4] = 1;
SD += (4,5); A[4,5] = 1;
SD += (5,6); A[5,6] = 1;
SD += (6,7); A[6,7] = 1;
SD += (6,8); A[6,8] = 1;
SD += (7,8); A[7,8] = 1;
g = new Graph(A);
writeln(g.A);

Answer 1

You should set the value of the vdom field during Phase 1 of initialization rather than relying on setting it during the default phase (Phase 2). Phase 1 handles the initial value of all fields, so if you don't set vdom explicitly, it will be {1..0, 1..0} when we make the initial value of the SD and A fields, which is why you are getting that error message.
proc init(A: []) {
this.vdom = {A.domain.dim(1), A.domain.dim(2)};
this.complete(); // insert this line here
for ij in A.domain {
this.SD += ij;
}
}
Edit: with executing your sample call line and my fix, I get the following as output:
0.0 0.0 0.0
0.0
0.0
0.0
0.0
0.0 0.0
0.0