Matlab Built-In Functions

Matlab → Basics → Variables → Built-In Functions

Suppose we want to find the square root of 16. It could easily be done in Matlab using the command >> sqrt(16). It shows the answer 4 when you press the Enter key. For example,

Command Window
>> sqrt(16) ans = 4

Matlab has several useful built-in functions. A few of them are listed in the following Table.

Mathematics	Command	Answer
$\sqrt{(80)}$ $\sqrt{(80+1)}$	`>> sqrt(81) >> sqrt(80+1)`	9 9
$e^5$ $e^{-6}$	`>> exp(5)` `>> exp(-6)`	148.4132 0.0025
$\|-10\|$	`>> abs(-10)`	10
$4!$ $5!$	`>> factorial(4)` `>> factorial(5)`	24 (4×3×2×1=24) 120 (5×4×3×2×1=120)
$ln1000$ $log1000$	`>> log(1000)` `>> log10(1000)`	6.9078 3
$\pi$	`>> pi`	3.1416
$sin\Big(\frac{\pi}{6}\Big)$ $sin30^0$	`>> sin(pi/6)` `>> sind(30)`	0.5000 0.5000
What is the remainder when 33 is divided by 5? What is the remainder when 134 is divided by 9?	`>> rem(33,5)` `>> rem(134,9)`	3 4

Example Suppose $2,000 is invested at a rate of 8% per year compounded continuously. How much will be the amount after:
(a) 4.2 years
(b) 5 years and 2 months

Solution:
(a) When $t=4.2$ , the Matlab code is

>> P=2000; r=0.08; t=4.2; >> A=P*exp(r*t) A = 2798.678

(b) When $t=5.1667$ (because 5 years and 2 months = $5+\frac{2}{12}=5.1667$ ), the Matlab code is

>> P=2000; r=0.08; t=5.1667; >> A=P*exp(r*t) A = 3023.706