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Matrix Manipulation

This example shows how to do some basic matrix manipulations in MATLAB®.

We start by creating a magic square and assigning it to the variable A.

A = magic(3)
A = 

     8     1     6
     3     5     7
     4     9     2

Here's how to add 2 to each element of A.

Note that MATLAB requires no special handling of matrix math.

A+2
ans = 

    10     3     8
     5     7     9
     6    11     4

The apostrophe symbol denotes the complex conjugate transpose of a matrix.

Here's how to take the transpose of A.

A'
ans = 

     8     3     4
     1     5     9
     6     7     2

The symbol * denotes multiplication of matrices.

Let's create a new matrix B and multiply A by B.

B = 2*ones(3)
B = 

     2     2     2
     2     2     2
     2     2     2

A*B
ans = 

    30    30    30
    30    30    30
    30    30    30

We can also multiply each element of A with its corresponding element of B by using the .* operator.

A.*B
ans = 

    16     2    12
     6    10    14
     8    18     4

MATLAB has functions for nearly every type of common matrix calculation. For example, we can find the eigenvalues of A using the "eig" command.

eig(A)
ans = 

   15.0000
    4.8990
   -4.8990

This concludes our brief tour of some MATLAB matrix handling capabilities.

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