RotationMatrix

RotationMatrix[θ]
gives the 2D rotation matrix that rotates 2D vectors counterclockwise by θ radians.

RotationMatrix[θ,w]
gives the 3D rotation matrix for a counterclockwise rotation around the 3D vector w.

RotationMatrix[{u,v}]
gives the matrix that rotates the vector u to the direction of the vector v in any dimension.

RotationMatrix[θ,{u,v}]
gives the matrix that rotates by θ radians in the hyperplane spanned by u and v.

DetailsDetails

  • RotationMatrix gives matrices for rotations of vectors around the origin.
  • Two different conventions for rotation matrices are in common use.
  • RotationMatrix is set up to use the vector-oriented convention and to give a matrix m so that yields the rotated version of a vector r.
  • Transpose[RotationMatrix[]] gives rotation matrices with the alternative coordinate-system-oriented convention for which yields the rotated version of a vector r.
  • Angles in RotationMatrix are in radians. θ Degree or θ specifies an angle in degrees.
  • Positive θ in RotationMatrix[θ,{u,v}] corresponds to going from the direction of u towards the direction of v.
  • RotationMatrix[θ] is equivalent to RotationMatrix[θ,{{1,0},{0,1}}].
  • RotationMatrix[θ,w] is equivalent to RotationMatrix[θ,{u,v}], where , , and form a right-handed coordinate system.
  • RotationMatrix gives an orthogonal matrix of determinant 1, that in dimensions can be considered an element of the group .

ExamplesExamplesopen allclose all

Basic Examples  (4)Basic Examples  (4)

General 2D rotation matrix for rotating a vector about the origin:

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Out[1]//MatrixForm=

Apply rotation by to a unit vector in the direction:

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Out[2]=

Counterclockwise rotation by 30°:

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Out[1]=

Rotation that transforms the direction of into the direction of :

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Out[1]=

3D rotation around the axis:

In[1]:=
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Out[1]//MatrixForm=
Introduced in 2007
(6.0)