A vector in MATLAB is a 1-dimensional array of numbers. You can work both with row vectors and column vectors.

Row and column vectors A row vector is created by putting the numbers in a list and separating them with a space or comma.

You get a column vector when you separate the components with semicolons.

Below are, behind the prompts in the MATLAB command window, commands to create a vector of any type. The final command illustrates that a transposed vector is obtained by means of an apostrophe.

>> rv = [4 5 6]      % row vector
rv =
     4     5     6
>> cv = [4; 5; 6]    % column vector  
cv =
     4
     5
     6
>> cv'      % transposed vector
ans =
     4     5     6

Dimension and norm With the length command you can determine the dimension of a vector. Do not confuse this with what is understood in mathematics by the (Euclidean) length of a vector, namely the norm. The norm can be calculated numerically in MATLAB with the command norm and there are options to calculate variations.

>> dimension = length(rv)
dimension =
     3
>> euclideanlength = norm(rv) % Euclidean length
lengte =
8.7750 >> norm1 = norm(rv,1) % sum of absolute values of components norm1 = 15 >> infnorm = norm(rv,inf) % maximum of absolute values of components infnorm = 6

Special constructions There are also special commands to create specific vectors; we show a few commonly used constructions.

>> v1 = 5:10      % from 5 up to and including 10
v1 =
     5     6     7     8     9    10
>> v2 = 10:-2:5    % from 10 down to and including 5 with steps of -2
v2 =
    10     8     6
>> v3 = linspace(0,1,6)   % equidistant distribution of 6 points in [0,1]
v3 =
         0    0.2000    0.4000    0.6000    0.8000    1.0000
>>  v4 = zeros(3,1)   % column vector with 3 zeros
v4 =
     0
     0
     0
>> v5 = ones(1,3,'logical')   % row vector with logical values 1
v5 =
  1×3 logical array
   1   1   1
>> v6 = []   % empty 0-dimensional vector 
v6 =
     []

Concatenating vectors You can create new vectors by concatenating vectors.

>> v1 = 1:3;   v2 = 4:6;   v12 = [v1 v2]
v12 =
     1     2     3     4     5    6

Randomly generated vectors In simulations you can make extensive use of vectors with randomly generated numbers, i.e., with random numbers. There are several instructions for this purpose.

rand random numbers between 0 and 1 using a uniform distribution
randi random numbers via a discrete uniform distribution
randn random numbers using the standard normal distribution

>> rand(1,5)   % 5 random numbers between 0 and 1
ans =
    0.7577    0.7431    0.3922    0.6555    0.1712
>> randi( [5,8], 1, 10 )   % 10 random integers between 5 en 8 (inclusive)
ans =
     8     7     7     8     8     7     5     5     8     5
>> randn(1,8)  % 8 random numbers generated from the standard normal distribution
ans =
   -0.0245   -1.9488    1.0205    0.8617    0.0012   -0.0708   -2.4863    0.5812
>> x = -5:0.5:5;
>> y = randn(1,10000);
>> h = histogram(y,x);     % construct a histogram from the data and plot it
>> set(h,'FaceColor','r','EdgeColor','w')   % adjust the diagram style 

histogramMATLAB.png

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