MATLAB Basics

Create a variable named a by typing this statement at the command line

>> a = 1

a =

1

Hide Result by adding (;) at end of statement.

>> a = 1;

When you do not specify an output variable, MATLAB uses the variable ans, short for answer, to store the results of your calculation.

>> sin(a)

ans =

0.8415

Built-in Functions:

>> d = cos(a)

d =

0.5403

 sin Sine of argument in radians sind Sine of argument in degrees asin Inverse sine in radians asind Inverse sine in degrees sinh Hyperbolic sine of argument in radians asinh Inverse hyperbolic sine cos Cosine of argument in radians cosd Cosine of argument in degrees acos Inverse cosine in radians acosd Inverse cosine in degrees cosh Hyperbolic cosine acosh Inverse hyperbolic cosine tan Tangent of argument in radians tand Tangent of argument in degrees atan Inverse tangent in radians atand Inverse tangent in degrees atan2 Four-quadrant inverse tangent

Square root:

>> sqrt(36)

ans =

6

Complex Numbers

Complex numbers have both real and imaginary parts, where the imaginary unit is the square root of -1.

To represent the imaginary part of complex numbers, use either i or j .

>> sqrt(-1)

ans =

0.0000 + 1.0000i

Workspace Variables

- MATLAB Is case-sensitive

The workspace contains variables that you create within or import into MATLAB from data files or other programs. For example, these statements create variables A and B in the workspace.

>> A = 9;

>> B = 10;

Workspace variables do not persist after you exit MATLAB. Save your data for later use with the save command.

>> save C:\myfile.mat

Saving preserves the workspace in your current working folder in a compressed file with a .mat extension, called a MAT-file.

To clear all the variables from the workspace, use the clear command.

>> clear

Restore data from a MAT-file into the workspace using load.

Text and Characters:

When you are working with text, enclose sequences of characters in single quotes. You can assign text to a variable.

>> myText = 'Hello, world';

• If the text includes a single quote, use two single quotes within the definition.

>> otherText = 'You''re right'

otherText =

'You're right'

You can concatenate character arrays with square brackets

>> longText = [myText,' - ',otherText]

longText =

'Hello, world - You're right'

To convert numeric values to characters, use functions, such as num2str or int2str.

>> f = 71;

>> c = (f-32)/1.8;

>> tempText = ['Temperature is ',num2str(c),'C']

tempText =

'Temperature is 21.6667C'

• Factorial of input

>> f = factorial(9)

f =

362880

• Absolute value and complex magnitude

>> y = abs(-9);

• Quotient of integer division

>> floor(23/5);

• remainder

>> rem(23,5);

>> mod(23,5);

• Integer Part

>> fix (23/5);

• Real nth root of real numbers

>> Y = nthroot(16,4);

• Is Prime numbers

>> isprime (5);

>> factor (30);

• Convert to Base System
 base2dec Convert base N number string to decimal number bin2dec Convert binary number string to decimal number dec2base Convert decimal to base N number in string dec2bin Convert decimal to binary number in string dec2hex Convert decimal to hexadecimal number in string hex2dec Convert hexadecimal number string to decimal number hex2num Convert hexadecimal number string to double-precision number num2hex Convert singles and doubles to IEEE hexadecimal strings