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# isTranslation

Determine if geometric transformation is pure translation

## Syntax

``TF = isTranslation(tform)``

## Description

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````TF = isTranslation(tform)` determines whether or not the rigid or affine transformation specified by `tform` is a pure translation.```

## Examples

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Create an `affine2d` object that defines a pure translation.

```A = [ 1 0 0 0 1 0 40 40 1 ]; tform = affine2d(A)```
```tform = affine2d with properties: T: [3x3 double] Dimensionality: 2 ```

Check if the transformation is a pure translation.

```tf = isTranslation(tform) ```
```tf = 1```

Create an `affine3d` object that defines a different scale factor in each dimension.

```Sx = 1.2; Sy = 1.6; Sz = 2.4; tform = affine3d([Sx 0 0 0; 0 Sy 0 0; 0 0 Sz 0; 0 0 0 1]);```
```tf = affine3d with properties: T: [4x4 double] Dimensionality: 3```

Check if the transformation is a pure translation. Since `tform` scales the object,

`tf = isTranslation(tform)`
```tf = 0```

As expected, the transformation is not a pure translation since scaling changes the size and shape of an input volume.

## Input Arguments

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Geometric transformation, specified as an `affine2d`, `affine3d`, or `rigid2d` geometric transformation object.

## Output Arguments

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Geometric transformation is pure translation, returned as `true` or `false`.

Data Types: `logical`

## More About

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### Translation Transformation

A translation transformation shifts an image without modifying the image size, shape, or orientation. A 2-D translation is represented by a matrix `T` of the form:

``` [1 0 0; 0 1 0; e f 1]; ```

A 3-D translation is represented by a matrix of the form:

``` [1 0 0 0; 0 1 0 0; 0 0 1 0; j k l 1]; ```

## Version History

Introduced in R2013a