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.
>> load C:\myfile.mat
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 |