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The behavior of the MATLAB environment is like a super complex calculator. You can enter commands at the >> command prompt.
MATLAB is an interpreted environment. In other words, you give a command, and MATLAB executes the command immediately.
Enter a valid expression, such as,
5 + 5
Then press ENTER
When you click the Execute button or type Ctrl + When E is used, MATLAB will execute it immediately, and the returned result is-
ans = 10
Let's take a few more examples-
3 ^ 2 % 3 raised to the power of 2
When you click the Execute button or type Ctrl + When E is used, MATLAB will execute it immediately, and the returned result is-
ans = 9
Another example,
sin(pi /2) % Sine of angle 90o
When you click the Execute button or type Ctrl + When E is used, MATLAB will execute it immediately, and the returned result is-
ans = 1
Another example,
7/0 % Divide by zero
When you click the Execute button or type Ctrl + When E is used, MATLAB will execute it immediately, and the returned result is-
ans = Inf warning: division by zero
Another example,
732 * 20.3
When you click the Execute button or type Ctrl + When E is used, MATLAB will execute it immediately, and the returned result is-
ans = 1.4860e+04
MATLAB provides some special expressions for certain mathematical symbols, such as pi representing π, Inf representing ∞, i (and j) representing √-1et al.NanRepresents 'not a number'.
The semicolon (;) indicates the end of a statement. However, if you want to hide and hide the output of an expression in MATLAB, add a semicolon after the expression.
For example,
x = 3; y = x + 5
When you click the Execute button or type Ctrl + When E is used, MATLAB will execute it immediately, and the returned result is-
y = 8
The percentage sign (%) is used to indicate comment lines. For example,
x = 9 % Assign value9Assign to x
You can also use block comment operators %{} to write comment blocks.
The MATLAB editor includes tools and context menu items that can help you add, delete, or change the format of comments.
MATLAB supports the following commonly used operators and special characters-
| Operator | Destination |
|---|---|
| + | Addition; addition operator. |
| - | Subtraction; subtraction operator. |
| * | Scalar and matrix multiplication operator. |
| .* | Array multiplication operator. |
| ^ | Scalar and matrix power operator. |
| .^ | Array power operator. |
| \ | Left division operator. |
| / | Right division operator. |
| .\ | Array left division operator. |
| ./ | Array right division operator. |
| : | Colon; generate elements with regular spacing and represent entire rows or columns. |
| ( ) | Parentheses; enclose function parameters and array indices; rewrite precedence. |
| [ ] | Brackets; attach array elements. |
| . | Decimal point. |
| ... | Ellipsis; line continuation operator |
| , | Comma; separate statements and elements in a row |
| ; | Semicolon; separate columns and suppress display. |
| % | Percent sign; specify comments and specify format. |
| _ | Reference symbol and transpose operator. |
| ._ | Nonconjugated transpose operator. |
| = | Assignment operator. |
MATLAB supports the following special variables and constants-
| Name | Meaning |
|---|---|
| ans | The latest calculated answer. |
| eps | Floating-point precision. |
| i,j | Imaginary unit √-1. |
| Inf | Infinite. |
| NaN | Undefined numeric results (not numbers). |
| pi | π |
Variable names are composed of letters followed by any number of letters, numbers, or underscores.
MATLAB is case-sensitive.
Variable names can be of any length, but MATLAB only uses the first N characters, where N is given by the function namelengthmax.
saveThe command is used to save all variables in the workspace as files with the .mat extension in the current directory.
For example,
save myfile
You can use it at any time in the futureloadCommand to reload the file.
load myfile