Python tutorial
Python Operators
Operators are used to perform operations on variables and values.
Python divides the operators in the following groups:
- Arithmetic operators
- Assignment operators
- Comparison operators
- Logical operators
- Identity operators
- Membership operators
- Bitwise operators
Python Arithmetic Operators
Arithmetic operators are used with numeric values to perform common mathematical operations:
| operator | name | Example | values for x and y | output |
|---|---|---|---|---|
| + | Addition | x + y | print(5+3) | 8 |
| - | Subtraction | x - y | print(5-3) | 2 |
| * | Multiplication | x * y | print(5*3) | 15 |
| / | Division | x / y | print(12/3) | 4 |
| % | Modulus | x%y | print(5%2) | 1 |
| ** | Exponentiation | x**y | print(2**5) | 32 |
| // | Floor Division | x//y | print(12//2) | 7 |
Python Assignment Operators
Assignment operators are used to assign values to variables:
| Oprator | Example | Same as | output |
|---|---|---|---|
| = | x=5 | x=5 | 5 |
| += | x+=3 | x=x+3 | 8 |
| -= | x-=3 | x=x-3 | 2 |
| *= | x*=3 | x=x*3 | 15 |
| /= | x/=3 | x=x/3 | 1.666 |
| %= | x%=3 | x=x%3 | 2 |
| //= | x//=3 | x=x//3 | 1 |
| **= | x**=3 | x=x**3 | 125 |
| &= | x&=3 | x=x&3 | 1 |
| |= | x|=3 | x=x|3 | 7 |
| ^= | x^=3 | x=x^3 | 6 |
| >>= | x>>3 | x=x>>3 | 0 |
| <<= | x<<3 | x=x<<3 | 40 |
Python Comparison Operators
Comparison operators are used to compare two values:
| Operator | Name | example | values | output |
|---|---|---|---|---|
| == | Equal | x==y | print(5==3) | False |
| != | Not equal | x!=y | print(5!=3) | True |
| > | Greater than | x>y | print(5>3) | True |
| < | Less than | x<y | print(5<3) | False |
| >= | Greater than or equal to | x>=y | print(5>=3) | True |
| <= | Less than or equal to | x<=y | print(5<=3) | False |
Python Logical Operators
Logical operators are used to combine conditional statements:
| Operator | Description | eaxample | output |
|---|---|---|---|
| and | Returns True if both statements are true | print(5 > 3 and 5 < 10) | True |
| or | Returns True if one of the statements is true | print(5 > 3 or 5 < 4) | True |
| not | Reverse the result, returns False if the result is true | print(not(5 > 3 and 5 < 10)) | False |
Python Identity Operators
Identity operators are used to compare the objects, not if they are equal, but if they are actually the same object, with the same memory location:
| Operator | Description | eaxample | output |
|---|---|---|---|
| is | Returns true if both variables are the same object |
x = ["apple", "banana"] print(x is z) print(x is y) print(x == y) |
False True |
| is not | Returns true if both variables are not the same object |
x = ["apple", "banana"] print(x is not z) print(x is not y) print(x != y) |
True False |
Python Membership Operators
Membership operators are used to test if a sequence is presented in an object:
| Operator | Description | eaxample | output |
|---|---|---|---|
| in | Returns True if a sequence with the specified value is present in the object |
x = ["apple", "banana"] print("banana" in x) |
True |
| not in | Returns True if a sequence with the specified value is not present in the object |
x = ["apple", "banana"] print("pineapple" not in x) |
True |
Python Bitwise Operators
Bitwise operators are used to compare (binary) numbers:
| Operator | Name | Description |
|---|---|---|
| & | AND | Sets each bit to 1 if both bits are 1 |
| | | OR | Sets each bit to 1 if one of two bits is 1 |
| ^ | XOR | Sets each bit to 1 if only one of two bits is 1 |
| ~ | NOT | Inverts all the bits |
| << | Zero fill left shift | Shift left by pushing zeros in from the right and let the leftmost bits fall off |
| >> | Signed right shift | Shift right by pushing copies of the leftmost bit in from the left, and let the rightmost bits fall off |