# An Introduction to Python For Undergraduate Engineers/Matrices

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Matrices can be created in the following way:

mymatrix = Matrix([[1,2],[3,4]])

In this example, `[1,2]` produces the first line of the matrix and `[2,3]` creates the second.

## Quick Standard Matrices[edit]

The following built in functions can be used to quickly create some standard matrices of specified size.

Command | Description | Example |
---|---|---|

eye() |
Identity Matrix | eye(4) creates a 4x4 identity matrix |

zeros() |
Empty Matrix | zeros(2,3) creates a 2x3 matrix of zeros |

ones() |
Matrix of 1s | ones(2) creates a 2x2 matrix of ones |

## Getting the Size of a Matrix[edit]

You can find out the size of a matrix using the *.shape[]* command, for example:

mymatrix.shape[0]

Command | Description |
---|---|

.shape[0] | Gives number of rows |

.shape[1] | Gives number of columns |