Edge List Induced Subgraph Selector
Select the vertex-induced edge observations for an explicit vertex set, preserving isolated declared vertices and occurrence identities.
Description
Select the vertex-induced edge observations for an explicit vertex set, preserving isolated declared vertices and occurrence identities.
An induced subgraph keeps every supplied edge whose two endpoints lie in the selected vertex set.
When to use this tool
Select the vertex-induced edge observations for an explicit vertex set, preserving isolated declared vertices and occurrence identities.
- Prepare the supplied edgesJson, vertices fields for this operation.
- Compare the complete example with the representation used by your own input before carrying the result into another step.
How to use the tool and how it works
- Enter edgesJson, vertices. Use the exact text syntax, units and index conventions explained below.
- Run the tool. If input validation fails, correct the supplied fields before interpreting any result.
- Read result.edges, result.vertices. Interpret false, null and empty lists using the distinctions below; they can be valid outputs.
Require unique vertices, return that list unchanged and filter edges to those with both endpoints selected.1
| Input field | Meaning and representation | Accepted input |
|---|---|---|
| edgesJson | JSON text, entered as one text field. The decoded structure is illustrated below; it is not a separate file. | Text |
| vertices | vertices. | List of strings; at most 128 entries |
For the JSON text fields, the following decoded structures show the example records before they are serialized into input strings. Keep field names, list nesting and value types as shown.
[
{
"field": "edgesJson",
"decoded": [
{
"id": "a",
"source": "u",
"target": "v",
"weight": 2
},
{
"id": "b",
"source": "v",
"target": "u",
"weight": 4
},
{
"id": "c",
"source": "u",
"target": "u",
"weight": 1
}
]
}
]| Output field | Interpretation |
|---|---|
| result | Object containing the named outputs below. |
| result.edges | The edges list in the ordering and representation described above. |
| result.vertices | The vertices list in the ordering and representation described above. |
{
"input": {
"edgesJson": "[{\"id\":\"a\",\"source\":\"u\",\"target\":\"v\",\"weight\":2},{\"id\":\"b\",\"source\":\"v\",\"target\":\"u\",\"weight\":4},{\"id\":\"c\",\"source\":\"u\",\"target\":\"u\",\"weight\":1}]",
"vertices": [
"u"
]
},
"output": {
"result": {
"edges": [
{
"id": "c",
"source": "u",
"target": "u",
"weight": 1
}
],
"vertices": [
"u"
]
}
}
}Limitations and assumptions
- Selected isolated labels remain in the returned vertex list. No graph closure, connected-component selection or edge-weight policy is applied.
- Every edge record requires unique string id, string source/target and finite numeric weight, even when this operation does not use the weight. Parallel endpoints and loops are retained unless explicitly filtered.
- Every declared top-level field is required and unexpected fields are rejected. Numeric inputs must be finite; ordinary text fields are bounded to 8,192 UTF-16 code units, with tighter operation-specific limits where stated.
- Lists are limited to 128 entries. JSON text must meet bounded size and depth checks, and numeric outputs beyond the safe finite magnitude are rejected. Exact large integers use decimal strings.
- Indexes are zero-based and spans have an exclusive end unless explicitly stated otherwise. A valid false, null or empty-list result is distinct from malformed input.
Alternative or Complementary methods
Choose edge identities, directedness and vertex coverage explicitly. Local edge-list audits and transformations do not replace a graph algorithm with the required connectivity, path or ordering guarantees.
References
Similar or alternative tools
- Edge ID Trail Validity Check
Verify an edge-ID trail with no repeated edge occurrences from an explicit start; directed or undirected traversal, with failure indexes retained.
- Edge List Boundary Cut Selector
Select edges crossing an explicit vertex-set boundary using endpoint exclusive membership; direction and occurrence IDs remain intact.