MATLAB Cheat Sheet: Functions, Operators, Loops and Plotting Syntax

Trigonometric Functions

Trig functions (in radians): sin(x), cos(x), tan(x), acos(x), asin(x), atan(x), cosh(x), sinh(x), csc(x), sec(x), and more.

Logarithm and Exponential Functions

• exp(x): e^x
• log(x): natural logarithm (log_e(x))
• log10(x): base-10 logarithm
• log2(x): base-2 logarithm
• sqrt(x): square root

Complex Numbers

• i or j: reserved for √(-1) unless otherwise designated
• abs(x): absolute value
• real(x): real part of a number
• imag(x): imaginary part of a number

Rounding Functions

• fix(x): round towards zero
• floor(x): round towards -∞
• ceil(x): round towards +∞
• round(x): round to the nearest integer

Predefined Constants

• pi = 3.14159...
• i, j = −1 (imaginary unit)
• Inf = infinity

Arrays and Matrices

• x = [1 2 3 4 5 6 7 8 9 10];: row vector with 10 columns
• x = [1; 2; 3; 4; 5; 6; 7; 8; 9; 10];: column vector with 10 rows
• A = [1 2; 3 4];: 2×2 matrix
• .*, ./, .^: element-wise operations on arrays
• linspace(a,b,c): creates a linearly spaced array from a to b with c points
• logspace(a,b,c): creates a logarithmically spaced vector from 10^a to 10^b with c points
• ones(m,n) and zeros(m,n): create an m×n matrix of ones or zeros

Plotting

• figure: generates a new figure window
• plot: creates a two-dimensional plot
• xlabel('Label'), ylabel('Label'), title('Title')

Line Styles

• - solid
• : dotted
• -. dash-dot
• -- dashed
• none no line

Colors

• b blue
• g green
• r red
• c cyan
• m magenta
• y yellow
• k black
• w white

Markers

• . point
• o circle
• x x-mark
• + plus
• * star
• s square
• d diamond
• v triangle (down)
• ^ triangle (up)
• < triangle (left)
• > triangle (right)
• p pentagram
• h hexagram

Workspace and Command Window Commands

• help topic: help on a specific topic
• who: list variables in the workspace
• whos: list variables with their sizes
• clear: clears the workspace
• clear x y: clears variables x and y
• clc: clears the command window
• clf: clears the figure
• pwd: shows the current directory
• cd: changes directory
• dir or ls: lists directory contents
• mkdir: makes a directory
• clock: gets the current time
• date: gets the current date
• quit or exit: quits MATLAB

Relational and Logical Operators

• > greater than
• < less than
• ~= not equal to
• == equal to
• <= less than or equal to
• >= greater than or equal to
• && and (both true)
• || or (one or both true)
• ~ not
• xor exclusive or (one true, one false)

Control Flow Syntax

if value > othervalue
    actions
elseif value ~= othervalue
    actions2
else
    actions3
end

for variable = 1:1:n
    actions
end

while x <= 10
    actions
end

Common Loop Patterns

y = zeros(1,10);
for count = 1:10
    y(count) = _______
end

A = zeros(3,3);
for i = 1:3
    for j = 1:3
        A(i,j) = ____
    end
end

sumx = 0;
for i = 1:n
    sumx = sumx + x(i);
end