Basic Math
Objective
• Use Matlab to solve numeric equations.
Background
The usual arithmetic operations
Math Operation
Addition
Subtraction
Multiplication
Division
Exponentiation
Parenthesis
Matlab Symbol
+
*
/
^
()
Note:
It is standard to only use () as parenthesis, as [] and {}
are used in Matlab for Matrices and Cells, respectively
Order of Operations
Please Excuse My Dear Aunt Sally
• P = Parenthesis
• E = Exponents
• M = Multiply
• D = Divide
• A = Add
• S = Subtract
Example:
1Τ
-1^(1/2) is −1 2 = -1
whereas (-1)^(1/2) is −1 = i (imaginary #)
1
−1
and -1^1/2 is ൗ2 = −0.5000
Syntax
Basic Math Operators
Division Operator Examples:
6/3 = 2
6\3 = 0.5
Exponent Example:
2^3 = 8
Predefined Numbers
•π
• Syntax: pi
• MATLAB represents pi using the floating point value closest to pi
• 𝑒𝑥
• Syntax: exp(x)
• Factorials (i.e. 5!)
• Syntax: factorial(5)
Example
In Matlab
Built-In
Functions
Long Division
Numeric Functions
Basic Syntax
ceil
Rounds to the nearest integer, towards ∞
Y = ceil(X)
fix
Rounds to the nearest integer, towards zero
Y = fix(X)
floor
Rounds to the nearest integer, towards -∞
Y = floor(X)
round
Rounds to the nearest integer
Y = round(X)
rem
returns the remainder after division of a by b, where a is
the dividend and b is the divisor
r = rem(a,b)
mod
returns the remainder after division of a by m, where a is
the dividend and m is the divisor
b = mod(a,m)
abs
Absolute Value |x|
A = abs(x)
Exponents / Logs
Trigonometry Refresher
MATLAB Trigonometry (sin & cos)
MATLAB Trigonometry (tan & cot)
MATLAB Trigonometry (sec & csc)
Logarithms
Math:
ln(5)
log10(5) or log(5)
log2(5)
Matlab: log(5)
log10(5)
log2(5)
Excel:
LOG10(5)
LOG(5,2)
LN(5)