MATLAB Octave CLI

Internal

• MATLAB/Octave
• MATLAB/Octave Concepts

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Prompt

PS1('>> ')

In-Line Operations

1 + 2
2 - 1
1 * 2, 2 * C % where C is a matrix
2 / 1
2 ^ 6 

Logical operations

Equality:

1 == 2

Non-equality:

1 ~= 2

Logical AND:

1 && 0

Logical OR:

1 || 0

Variable Assignment

Also see:

Variables

Scalar Variable Assignment

<scalar-variable-name> = <variable-value>

Vector Variable Assignment

Vector

Assignment and literal initialization:

<vector-variable-name> = [ v1 v2 v3 ... ] % An (1, n) vector
<vector-variable-name> = [ v1; v2; v3; ... ] % An (n, 1) vector

Other Types of Vector Initialization

Start from "start-value" (inclusively), increment with "increment-step" until the value is strictly larger than "end-value":

v = <start-value>:<increment-step>:<end-value>

Start from "start-value" to "end:value" with increments of 1:

v = <start-value>:<end-value>

v = zeros(1, 3)
v = zeros(3, 1)
v = ones(1, 3)
v = ones(3, 1)

Matrix Variable Assignment

Matrix

Assignment and literal initialization:

<two-dimensional-matrix-variable-name> = [ v11 v12 ... v1n;  v21 v22 ... v2n; ...; vm1 vm2 ... vmn ] % A (m, n) matrix.

Other Types of Matrix Initialization

C = zeros(2, 3)
C = ones(2, 3)

Initialization Functions

zeros

v = zeros(1, 3)
C = zeros(2, 3)

ones

v = ones(1, 3)
C = ones(2, 3)

eye

Identity matrix

C = eye(3)

rand

v = rand(1, 3)
C = rand(2, 3)

randn

Gaussian.

v = randn(1, 3)
C = randn(2, 3)

Data Size

size

size()

Dimensions of a matrix:

size(A)

Returns a vector with two elements (number of rows and number of columns).

Number of rows of a matrix:

size(A, 1)

Number of columns of a matrix:

size(A, 2)

length

Should only be applied to vectors, for matrices is confusing.

Printing

To print the value of the variable, simply type the name of the variable:

<variable-name>

disp

disp(<variable-name>)

Also see format.

printf

printf
fprintf
sprintf

a = pi;
sprintf('this is pi with 6 decimals %0.6f', a);

Also see:

Generic printf

format

Reset or specify the format of the output produced by disp and the normal output mechanism.

Also see:

Display

short

Fixed point format with 5 significant figures in a field that is a maximum of 10 characters wide.

Filesystem

cd

Modify the current directory.

pwd

Print working directory.

clear

Delete the names matching the pattern from the symbol table. The pattern is a simplified regular expression, with '?', '*', '[...]'. With no arguments, all user-define variables (local and global) are deleted.

close

Close figure windows.

clc

Clears the terminal screen and move the cursor to the upper left corner.

fprintf

Like printf, just that the output is written to the FID stream instead of stdout.

load

Load the named variables from the file. If no variables are named, all variables found in the file will be loaded.