Programming |

**Empty Matrices, Scalars, and Vectors**

Although matrices are two dimensional, they do not always appear to have a rectangular shape. A 1-by-8 matrix, for example, has two dimensions yet is linear. These matrices are described in the following sections:

An

*empty matrix*has one of more dimensions that are equal to zero. A two-dimensional matrix with both dimensions equal to zero appears in MATLAB as`[]`

. The expression`A = []`

assigns a 0-by-0 empty matrix to`A`

.

A

*scalar*is 1-by-1 and appears in MATLAB as a single real or complex number (e.g.,`7`

,`583.62`

,`-3.51`

,`5.46097e-14`

,`83+4i`

).

Returning a Triangular Portion of a Matrix | The Empty Matrix |

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