# MATLAB Language Initializing Matrices or arrays

## Introduction

Matlab has three important functions to create matrices and set their elements to zeroes, ones, or the identity matrix. (The identity matrix has ones on the main diagonal and zeroes elsewhere.)

## Syntax

• Z = zeros(sz,datatype,arraytype)
• X = ones(sz,datatype)
• I = eye(sz,datatype)

## Parameters

ParameterDetails
szn (for an n x n matrix)
szn, m (for an n x m matrix)
szm,n,...,k (for an m-by-n-by-...-by-k matrix)
datatype'double' (default), 'single', 'int8', 'uint8', 'int16', 'uint16', 'int32', 'uint32', 'int64', or 'uint64'
arraytype'distributed'
arraytype'codistributed'
arraytype'gpuArray'

## Remarks

These functions will create a matrix of doubles, by default.

## Creating a matrix of 0s

``````z1 = zeros(5); % Create a 5-by-5 matrix of zeroes
z2 = zeros(2,3); % Create a 2-by-3 matrix
``````

## Creating a matrix of 1s

``````o1 = ones(5); % Create a 5-by-5 matrix of ones
o2 = ones(1,3); % Create a 1-by-3 matrix / vector of size 3
``````

## Creating an identity matrix

``````i1 = eye(3); % Create a 3-by-3 identity matrix
i2 = eye(5,6); % Create a 5-by-6 identity matrix
``````