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rigid2d

(Not recommended) 2-D rigid geometric transformation using postmultiply convention

rigid2d is not recommended. Use the rigidtform2d object instead. For more information, see Compatibility Considerations.

Description

A rigid2d object stores information about a 2-D rigid geometric transformation and enables forward and inverse transformations.

Creation

Description

tform = rigid2d creates a default rigid2d object that corresponds to an identity transformation.

tform = rigid2d(t) sets the T property as the specified 2-D rigid transformation matrix t.

example

tform = rigid2d(rot,trans) sets the Rotation and Translation properties as the specified rotation matrix rot and translation vector trans, respectively.

Properties

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Forward rigid transformation, specified as a 3-by-3 numeric matrix. The matrix T satisfies the postmultiply convention given by:

[x y 1] = [u v 1] * Rotation + Translation

Data Types: single | double

Rotation component of the transformation, specified as a 2-by-2 numeric matrix.

Data Types: single | double

Translation component of the transformation, specified as a 2-element numeric row vector.

Data Types: single | double

This property is read-only.

Dimensionality of the geometric transformation, specified as the number 2.

Object Functions

invertInvert geometric transformation
isTranslationDetermine if geometric transformation is pure translation
outputLimitsFind output spatial limits given input spatial limits
transformPointsForwardApply forward geometric transformation
transformPointsInverseApply inverse geometric transformation

Examples

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Specify an angle of rotation in degrees and create a 2-by-2 rotation matrix.

theta = 30;
rot = [ cosd(theta) sind(theta); ...
       -sind(theta) cosd(theta)];

Specify the amount of horizontal and vertical translation, respectively.

trans = [2 3];

Create a rigid2d object that performs the rotation and translation.

tform = rigid2d(rot,trans)
tform = 
  rigid2d with properties:

       Rotation: [2x2 double]
    Translation: [2 3]

Extended Capabilities

Version History

Introduced in R2020b

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