randomGraphRandomForwardEdges doesn't add edges when connected=true

[jmogarrio]

The following check at line 343 occurs before any edge insertion. When connected=true, the continue statement is always executed, so the output has no edges.

        if (connected && indegree == 0 && outdegree == 0) {
            i--;
            continue;
        }

[jdramsey]

Try changing it to this:

int trials = 0;
boolean added = false;

for (int i = 0; i < numEdges; i++) {
    int c1 = RandomUtil.getInstance().nextInt(nodes2.size());
    int c2 = RandomUtil.getInstance().nextInt(nodes2.size());

    if (++trials > 2 * numEdges) break;

    if (c1 == c2) {
        i--;
        continue;
    }

    if (c1 > c2) {
        int temp = c1;
        c1 = c2;
        c2 = temp;
    }

    Node n1 = nodes2.get(c1);
    Node n2 = nodes2.get(c2);

    if (dag.isAdjacentTo(n1, n2)) {
        i--;
    }

    final int indegree = dag.getIndegree(n2);
    final int outdegree = dag.getOutdegree(n1);

    if (indegree >= maxIndegree) {
        i--;
        continue;
    }

    if (outdegree >= maxOutdegree) {
        i--;
        continue;
    }

    if (dag.getIndegree(n1) + dag.getOutdegree(n1) + 1 > maxDegree) {
        i--;
        continue;
    }

    if (dag.getIndegree(n2) + dag.getOutdegree(n2) + 1 > maxDegree) {
        i--;
        continue;
    }

    if (added && connected && indegree == 0 && outdegree == 0) {
        i--;
        continue;
    }

    dag.addDirectedEdge(n1, n2);
    added = true;
}

fixLatents4(numLatentConfounders, dag);

GraphUtils.circleLayout(dag, 200, 200, 150);

return dag;

}

Joe

On Fri, Dec 11, 2015 at 4:37 PM, jmogarrio notifications@github.com wrote:

The following check at line 343 occurs before any edge insertion When connected=true, the continue statement is always executed, so the output has no edges

    if (connected && indegree == 0 && outdegree == 0) {
        i--;
        continue;
    }

— Reply to this email directly or view it on GitHub https://github.com/cmu-phil/tetrad/issues/102.

Joseph D. Ramsey Special Faculty and Director of Research Computing Department of Philosophy 135 Baker Hall Carnegie Mellon University Pittsburgh, PA 15213

jsph.ramsey@gmail.com Office: (412) 268-8063 http://www.andrew.cmu.edu/user/jdramsey

[jmogarrio]

The number of edges is really small. Running it with arguments (1000, 250, 1000, 30, 15, 15, true) returns graphs with number of edges in the order of 10.

I don't really need the connectedness, it just seems the method is not working as it seems it's supposed to.

Try changing it to this:

int trials = 0;
boolean added = false;

for (int i = 0; i < numEdges; i++) {
    int c1 = RandomUtil.getInstance().nextInt(nodes2.size());
    int c2 = RandomUtil.getInstance().nextInt(nodes2.size());

    if (++trials > 2 * numEdges) break;

    if (c1 == c2) {
        i--;
        continue;
    }

    if (c1 > c2) {
        int temp = c1;
        c1 = c2;
        c2 = temp;
    }

    Node n1 = nodes2.get(c1);
    Node n2 = nodes2.get(c2);

    if (dag.isAdjacentTo(n1, n2)) {
        i--;
    }

    final int indegree = dag.getIndegree(n2);
    final int outdegree = dag.getOutdegree(n1);

    if (indegree >= maxIndegree) {
        i--;
        continue;
    }

    if (outdegree >= maxOutdegree) {
        i--;
        continue;
    }

    if (dag.getIndegree(n1) + dag.getOutdegree(n1) + 1 > maxDegree) {
        i--;
        continue;
    }

    if (dag.getIndegree(n2) + dag.getOutdegree(n2) + 1 > maxDegree) {
        i--;
        continue;
    }

    if (added && connected && indegree == 0 && outdegree == 0) {
        i--;
        continue;
    }

    dag.addDirectedEdge(n1, n2);
    added = true;
}

fixLatents4(numLatentConfounders, dag);

GraphUtils.circleLayout(dag, 200, 200, 150);

return dag;

}

Joe

On Fri, Dec 11, 2015 at 4:37 PM, jmogarrio notifications@github.com wrote:

The following check at line 343 occurs before any edge insertion When connected=true, the continue statement is always executed, so the output has no edges

    if (connected && indegree == 0 && outdegree == 0) {
        i--;
        continue;
    }

— Reply to this email directly or view it on GitHub https://github.com/cmu-phil/tetrad/issues/102.

Joseph D. Ramsey Special Faculty and Director of Research Computing Department of Philosophy 135 Baker Hall Carnegie Mellon University Pittsburgh, PA 15213

jsph.ramsey@gmail.com Office: (412) 268-8063 http://www.andrew.cmu.edu/user/jdramsey

---

Reply to this email directly or view it on GitHub: https://github.com/cmu-phil/tetrad/issues/102#issuecomment-164054906

[jdramsey]

This is fixed, I think. There was also a problem in that the number of edges in the graph was not always what was requested, even for small graphs. This is also fixed.