# Documentation

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# isdag

Determine if graph is acyclic

## Syntax

``tf = isdag(G)``

## Description

example

````tf = isdag(G)` returns logical `1` (`true`) if `G` is a directed acyclic graph; otherwise, it returns logical `0` (`false`).```

## Examples

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Create and plot a directed graph, and then test the graph to determine if it is acyclic.

```s = [1 1 2 2 3 3 4 4 4 5]; t = [2 3 4 5 6 7 8 9 10 4]; G = digraph(s,t)```
```G = digraph with properties: Edges: [10x1 table] Nodes: [10x0 table] ```
`plot(G)`

`tf = isdag(G)`
```tf = logical 1 ```

## Input Arguments

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Input graph, specified as a `digraph` object. Use `digraph` to create a directed graph object.

Example: `G = digraph([1 2],[2 3])`

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### Directed Acyclic Graph (DAG)

A directed graph is acyclic if it contains no cycles. That is, starting at any node in the graph, no sequence of edges exists that can be followed to loop back to that starting node. As a result, directed acyclic graphs do not contain any self-loops.