Creating Matrices and Arrays

This example shows basic techniques for creating arrays and matrices using MATLAB. Matrices and arrays are the fundamental representation of information and data in MATLAB.

To create an array with multiple elements in a single row, separate the elements with either a comma ',' or a space. This type of array is called a row vector.

disp('Create an array with four elements in a single row:')
disp('>> a = [1 2 3 4]')
a = [1 2 3 4]

Create an array with four elements in a single row:
>> a = [1 2 3 4]

a =

     1     2     3     4

To create an array with multiple elements in a single column, separate the elements with semicolons ';'. This type of array is called a column vector.

disp('Create an array with four elements in a single column:')
disp('>> a = [1; 2; 3; 4]')
a = [1; 2; 3; 4]

Create an array with four elements in a single column:
>> a = [1; 2; 3; 4]

a =

     1
     2
     3
     4

To create a matrix that has multiple rows, separate the rows with semicolons.

disp('Create a matrix with three rows and three columns:')
disp('>> a = [1 2 3; 4 5 6; 7 8 9]')
a = [1 2 3; 4 5 6; 7 8 9]

Create a matrix with three rows and three columns:
>> a = [1 2 3; 4 5 6; 7 8 9]

a =

     1     2     3
     4     5     6
     7     8     9

To create an evenly spaced array, specify the start and end point by using the ':' operator.

disp('Create an array that starts at 1, ends at 9, with each element separated by 2:')
disp('>> x = 1:2:9')
x = 1:2:9

Create an array that starts at 1, ends at 9, with each element separated by 2:
>> x = 1:2:9

x =

     1     3     5     7     9

Another way to create a matrix is to use a function, such as ones, zeros or rand.

disp('Create a 1-by-5 matrix of 0''s:')
disp('>> z = zeros(1, 5)')
z = zeros(1, 5)

Create a 1-by-5 matrix of 0's:
>> z = zeros(1, 5)

z =

     0     0     0     0     0