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Cleaned up formatting and added headers (#20103)

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mistymayem
2018-11-03 21:10:30 -04:00
committed by Manish Giri
parent f3a1e18d3e
commit aa5e550c3b
1 changed files with 10 additions and 6 deletions
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guide/english/python/if-elif-else-statements/index.md
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@@ -4,8 +4,8 @@ title: If / Elif / Else Statements
## If / Elif / Else Statements ## If / Elif / Else Statements
The `if`/`elif`/`else` structure is a common way to control the flow of a program, allowing you to execute specific blocks of code depending on the value of some data. If the condition following the keyword `if` evaluates as `True`, the block of code will execute: The `if`/`elif`/`else` structure is a common way to control the flow of a program, allowing you to execute specific blocks of code depending on the value of some data. If the condition following the keyword `if` evaluates as `True`, the block of code will execute.
Note that parenthesis is not used before and after the condition check as in other languages. Note: that parenthesis is not used before and after the condition check as in other languages.
```python ```python
if True: if True:
print('If block will execute!') print('If block will execute!')
@@ -24,6 +24,7 @@ _Example_:
if 1: # 1 evaluates to true if 1: # 1 evaluates to true
print('If block will execute!') print('If block will execute!')
``` ```
***Else statement***
You can optionally add an `else` response that will execute if the condition is `False`: You can optionally add an `else` response that will execute if the condition is `False`:
```python ```python
@@ -44,6 +45,8 @@ else:
*Note that there is no condition following the `else` keyword - it catches all situations where the condition was `False`* *Note that there is no condition following the `else` keyword - it catches all situations where the condition was `False`*
***Elif statement***
Multiple conditions can be checked by including one or more `elif` checks after your initial `if` statement but only one condition will execute: Multiple conditions can be checked by including one or more `elif` checks after your initial `if` statement but only one condition will execute:
```python ```python
@@ -59,13 +62,14 @@ else:
print("Neither will I!") #this statement does not execute print("Neither will I!") #this statement does not execute
``` ```
*Note only the first condition that evaluates as `True` will execute. Even though `z > 6` is `True`, the `if/elif/else` block terminates after the first true condition. This means that an `else` will only execute if none of the conditions were `True`.* *Note: only the first condition that evaluates as `True` will execute. Even though `z > 6` is `True`, the `if/elif/else` block terminates after the first true condition. This means that an `else` will only execute if none of the conditions were `True`.*
***Nested if statement***
We can also create nested if statements for decision making. Before preceding please refer to the <a href='https://guide.freecodecamp.org/python/code-blocks-and-indentation' target='_blank' rel='nofollow'>indentation guide once</a> before preceding. We can also create nested if statements for decision making. Before preceding please refer to the <a href='https://guide.freecodecamp.org/python/code-blocks-and-indentation' target='_blank' rel='nofollow'>indentation guide once</a> before preceding.
Let's take an example of finding a number which is even and also greater than '10': Let's take an example of finding a number which is even and also greater than '10':
``` ```python
python
x = 34 x = 34
if x % 2 == 0: # this is how you create a comment and now, checking for even. if x % 2 == 0: # this is how you create a comment and now, checking for even.
if x > 10: if x > 10:
@@ -73,7 +77,7 @@ if x % 2 == 0: # this is how you create a comment and now, checking for even.
else: else:
print("This number is even, but not greater than 10") print("This number is even, but not greater than 10")
else: else:
print ("The number is not even. So point checking further.") print ("The number is not even. So no point checking further.")
``` ```
This was just a simple example for nested if statement. Please feel free to explore more online. This was just a simple example for nested if statement. Please feel free to explore more online.