# factorTwoPoseSE2

Factor relating two SE(2) poses

Since R2022a

## Description

The `factorTwoPoseSE2` object contains factors that relate pairs of poses in the SE(2) state space for a `factorGraph` object.

## Creation

### Syntax

``F = factorTwoPoseSE2(nodeID)``
``F = factorTwoPoseSE2(nodeID,Name=Value)``

### Description

````F = factorTwoPoseSE2(nodeID)` creates a `factorTwoPoseSE2` object, `F`, with the node identification numbers property `NodeID` set to `nodeID`.```

example

````F = factorTwoPoseSE2(nodeID,Name=Value)` specifies properties using one or more name-value arguments. For example, `factorTwoPoseSE2([1 2],Measurement=[1 5 7])` sets the `Measurement` property of the `factorTwoPoseSE2` object to `[1 5 7]`.```

## Properties

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Node ID numbers, specified as an N-by-2 matrix of nonnegative integers, where N is the total number of desired factors. Each row represents a factor that connects to two nodes of type `POSE_SE2` at the specified node IDs in the factor graph. The rows are of the form [PoseID PoseID].

If a factor in the `factorTwoPoseSE2` object specifies an ID that does not correspond to a node in the factor graph, the factor graph automatically creates a node of the required type with that ID and adds it to the factor graph when adding the factor to the factor graph.

You must specify this property at object creation.

Measured relative pose, specified as a N-by-3 matrix, where each row is of the form [dx dy dtheta]. N is the total number of factors. dx and dy are the change in position in x and y, respectively, and dtheta is the angle between the two positions.

Information matrix associated with the measurement, specified as a 3-by-3 matrix or a 3-by-3-N matrix. N is the total number of factors specified by this `factorTwoPoseSE2` object. Each information matrix corresponds to the measurements of the specified nodes in `NodeIDs`.

If you specify this property as a 3-by-3 matrix when `NodeID` contains more than one row, the information matrix corresponds to all measurements in `Measurement`.

## Object Functions

 `nodeType` Get node type of node in factor graph

## Examples

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Create measurement vector, information matrix, and a node ID number vector. Create a `factorTwoPoseSE2` object, specifying the node IDs, measurement, and information as arguments.

```nodeID = [1 2]; measure = [5 5 pi/2]; info = rand(3,3); f = factorTwoPoseSE2(nodeID,Measurement=measure,Information=info);```

Create a default factor graph and add the factor to the graph using the `addFactor` function.

```g = factorGraph; addFactor(g,f);```

## Version History

Introduced in R2022a

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