- Booleans have two possible values: True and False.
- They are denoted in Python as
TrueandFalse, respectively. - Booleans are the result of comparison operations or logical evaluations.
- Comparison operations compare values and produce boolean results (e.g.,
5 > 3yields True). - Logical operations (
and,or,not) combine boolean expressions. andreturns True only if both expressions are True.orreturns True if at least one expression is True.notreturns the inverse of the boolean expression.- Booleans are often used in conditional statements (
if,else,elif) to execute specific code blocks based on conditions. - Boolean values can be stored in variables to represent different states or conditions.
- To check if a value or variable is True or False, use the
bool()function.
**Method 1: Creating Booleans**
- Booleans can be created using the `True` and `False` literals.
```python
x = True
y = False
print(x) # Output: True
print(y) # Output: False
```
**Method 2: Comparison Operators**
- Comparison operators compare values and return boolean results.
```python
x = 5
y = 10
print(x == y) # Output: False
print(x != y) # Output: True
print(x > y) # Output: False
print(x < y) # Output: True
print(x >= y) # Output: False
print(x <= y) # Output: True
```
**Method 3: Logical Operators**
- Logical operators combine boolean expressions and return boolean results.
```python
x = True
y = False
print(x and y) # Output: False
print(x or y) # Output: True
print(not x) # Output: False
```
**Method 4: Conditional Statements (if-else)**
- Conditional statements execute blocks of code based on boolean expressions.
```python
x = 10
if x > 5:
print("x is greater than 5")
else:
print("x is less than or equal to 5")
```
**Method 5: Ternary Operator (Conditional Expression)**
- The ternary operator is a shorthand way to write simple if-else statements in a single line.
```python
x = 10
result = "x is greater than 5" if x > 5 else "x is less than or equal to 5"
print(result)
```
**Method 6: Boolean Conversion**
- You can convert other data types to booleans using the `bool()` function.
```python
print(bool(True)) # Output: True
print(bool(0)) # Output: False
print(bool("hello"))# Output: True
print(bool("")) # Output: False
```
**Method 7: Truthy and Falsy Values**
- In Python, certain values are considered truthy and others falsy when used in boolean contexts.
```python
print(bool([])) # Output: False
print(bool([1, 2])) # Output: True
print(bool(None)) # Output: False
print(bool(42)) # Output: True
```
**Method 8: Short-Circuit Evaluation**
- Logical operators `and` and `or` use short-circuit evaluation, stopping evaluation when the result is determined.
```python
x = 5
y = 10
if x > 0 and y / x > 2:
print("Condition is True")
```
Understanding these methods and using booleans effectively in your code will help you make logical decisions and control the flow of your Python programs.
ADVANCE
Certainly! Below are all the methods and their corresponding Python code examples related to booleans:
**Method 1: `bool()` function**
- The `bool()` function is used to convert values to booleans. Empty collections, None, and zero values will be converted to False, and non-empty values will be converted to True.
```python
# Converting different values to booleans
print(bool(True)) # True
print(bool(False)) # False
print(bool(0)) # False
print(bool(1)) # True
print(bool([])) # False
print(bool([1, 2])) # True
print(bool(None)) # False
print(bool("hello"))# True
```
**Method 2: Comparison Operators**
- Comparison operators are used to compare values and produce boolean results.
```python
x = 5
y = 10
print(x == y) # False
print(x != y) # True
print(x > y) # False
print(x < y) # True
print(x >= y) # False
print(x <= y) # True
```
**Method 3: Logical Operators**
- Logical operators (`and`, `or`, `not`) are used to combine boolean expressions and return boolean results.
```python
x = True
y = False
print(x and y) # False
print(x or y) # True
print(not x) # False
```
**Method 4: Conditional Statements (if-else)**
- Conditional statements are used to conditionally execute blocks of code based on boolean expressions.
```python
x = 10
if x > 5:
print("x is greater than 5")
else:
print("x is less than or equal to 5")
```
**Method 5: Ternary Operator (Conditional Expression)**
- The ternary operator is a shorthand way to write simple if-else statements in a single line.
```python
x = 10
result = "x is greater than 5" if x > 5 else "x is less than or equal to 5"
print(result)
```
**Method 6: Short-Circuit Evaluation**
- Logical operators `and` and `or` use short-circuit evaluation, which means they stop evaluating as soon as the result is determined.
```python
x = 5
y = 10
if x > 0 and y / x > 2:
print("Condition is True")
```
