Matlab
From charlesreid1
Matrices
Basics
Special matrices/vectors
| Name (matrix type) | Matlab syntax | Result |
|---|---|---|
| Ones | >> ones(3,2);
|
$ \left[ \begin{array}{cc} 1 & 1 \\ 1 & 1 \\ 1 & 1 \end{array} \right] $ |
| Zeros | >> zeros(3,1);
|
$ \left[ \begin{array}{cc} 0 \\ 0 \\ 0 \end{array} \right] $ |
| Eye (identity) | >> eye(3);
|
$ \left[ \begin{array}{ccc} 1 & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1 \end{array} \right] $ |
| Rand (random numbers) | >> rand(3,2);
|
$ \left[ \begin{array}{cc} 0.21955 & 0.27560\\ 0.42385 & 0.62212\\ 0.53343 & 0.69182 \end{array} \right] $ |
| Meshgrid | >> [x,y] = meshgrid(1:4,1:4);
|
$ x = \left[ \begin{array}{cccc} 1& 2& 3& 4\\ 1& 2& 3& 4\\ 1& 2& 3& 4\\ 1& 2& 3& 4 \end{array} \right] $
$ y = \left[ \begin{array}{cccc} 1& 1& 1& 1\\ 2& 2& 2& 2\\ 3& 3& 3& 3\\ 4& 4& 4& 4 \end{array} \right] $ |
| Magic (magic square matrix)
(The sum of each row and column is equal to the same value) |
>> magic(4);
|
$ \left[ \begin{array}{cccc} 16& 2& 3& 13\\ 5& 11& 10& 8\\ 9& 7& 6& 12\\ 4& 14& 15& 1 \end{array} \right] $ |
Functions
linspace
logspace
| Function name | Matlab syntax/output |
|---|---|
| det | Returns the determinant of a matrix:
>> A=magic(4)
A =
16 2 3 13
5 11 10 8
9 7 6 12
4 14 15 1
>> det(A)
ans = -1.4495e-12
|
| find | |
| flipud | |
| fliplr | |
| length | |
| max | |
| min | |
| repmat | This function creates a new matrix consisting of several copies of an existing matrix.
>> A = magic(3)
A =
8 1 6
3 5 7
4 9 2
>> repmat(A,2,2)
ans =
8 1 6 8 1 6
3 5 7 3 5 7
4 9 2 4 9 2
8 1 6 8 1 6
3 5 7 3 5 7
4 9 2 4 9 2
|
| size | |
| sort |
Operators
Input/output
Switches
Functions
Graphics
Examples
Fluid mechanics
Heat transfer
Optimization
Statistics
See also
- Introduction to Matlab (lecture)