Practice question · Sort into groups
Sort each object by how it is naturally represented.
Groups: Represented by a vector · Represented by a matrix
- The direction of a line in space
- A point in the plane
- A single displacement in space
- A rotation of the plane
- A dataset with rows as samples and columns as features
- The connections of a network
Hints
- Vectors hold one list of numbers; matrices hold a rectangular table of them.
- Anything relating each of several things to each of several others needs two indices.
Show the answer
Represented by a vector: A point in the plane, The direction of a line in space, A single displacement in space
Represented by a matrix: A rotation of the plane, A dataset with rows as samples and columns as features, The connections of a network
Why
Points, directions and displacements are single lists, vectors. Transformations, datasets and network connections all relate rows to columns and need two indices, matrices. Recognising which one a problem needs is the first step in the whole framework.
Practise Applications of Matrices and Vectors
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