[Introduction to Udemy Python3 + Application] 33. if statement

** * This article is from Udemy "[Introduction to Python3 taught by active Silicon Valley engineers + application + American Silicon Valley style code style](https://www.udemy.com/course/python-beginner/" Introduction to Python3 taught by active Silicon Valley engineers + application + American Silicon Valley style code style ")" It is a class notebook for myself after taking the course of. It is open to the public with permission from the instructor Jun Sakai. ** **

■ if statement

◆ Basics of if statement

if


x = -10

if x < 0:
    print('negative')

result


negative

You must put a `` (space) at the beginning of the line following the line that uses ʻif`. You only need one space, but Python has an implicit rule of four spaces.

else

else


x = 10

if x < 0:
    print('negative')
else:
    print('positive')
```

#### **`result`**
```python

positive
```
 By using ʻelse`, the case of" otherwise "can be specified.


◆`elif`

#### **`elif`**
```python

x = 0

if x < 0:
    print('negative')
elif x == 0:
    print('zero')
else:
    print('positive')
```

#### **`result`**
```python

zero
```
 ʻElif` is an abbreviation for "else if".
 By the way, ʻa == b` means "a and b are equal".
 (If a = b, b will be assigned to a)


##### ◆ if statement in if statement

#### **`if_in_if`**
```python

a = 1
b = 2

if a > 0:
    print('a is positive')
    if b > 0:
        print('b is also positive')
```

#### **`result`**
```python

a is positive
b is also positive
```
 At this time, the indent (indentation) of the second if statement must be aligned.


#### **`if_in_if`**
```python

a = 1
b = 2

if a > 0:
    print('a is positve')
     if b > 0:
        print('b is also positive')
```

#### **`result`**
```python

  File "/Users/fumiya/PycharmProjects/python_programming/lesson.py", line 6
    if b > 0:
    ^
IndentationError: unexpected indent
```
 An error occurred because the indentation was incorrect.


Recommended Posts

[Introduction to Udemy Python3 + Application] 33. if statement
[Introduction to Udemy Python3 + Application] 40.while else statement
[Introduction to Udemy Python3 + Application] 43. for else statement
[Introduction to Udemy Python 3 + Application] 31. Comments
[Introduction to Udemy Python 3 + Application] 57. Decorator
[Introduction to Udemy Python 3 + Application] 56. Closure
[Introduction to Udemy Python3 + Application] 59. Generator
[Introduction to Udemy Python 3 + Application] Summary
[Introduction to Udemy Python3 + Application] 68. Import statement and AS
[Introduction to Udemy Python3 + Application] 18. List methods
[Introduction to Udemy Python3 + Application] 63. Generator comprehension
[Introduction to Udemy Python3 + Application] 28. Collective type
[Introduction to Udemy Python3 + Application] 25. Dictionary-type method
[Introduction to Udemy Python3 + Application] 13. Character method
[Introduction to Udemy Python3 + Application] 55. In-function functions
[Introduction to Udemy Python3 + Application] 48. Function definition
[Introduction to Udemy Python 3 + Application] 10. Numerical values
[Introduction to Udemy Python3 + Application] 21. Tuple type
[Introduction to Udemy Python3 + Application] 45. enumerate function
[Introduction to Udemy Python3 + Application] 41. Input function
[Introduction to Udemy Python3 + Application] 17. List operation
[Introduction to Udemy Python3 + Application] 65. Exception handling
[Introduction to Udemy Python3 + Application] 11. Character strings
[Introduction to Udemy Python3 + Application] 44. range function
[Introduction to Udemy Python3 + Application] 46. Zip function
[Introduction to Udemy Python3 + Application] 24. Dictionary type
[Introduction to Udemy Python3 + Application] 8. Variable declaration
[Introduction to Udemy Python3 + Application] 29. Set method
[Introduction to Udemy Python3 + Application] 16. List type
[Introduction to Udemy Python3 + Application] 61. Dictionary comprehension
[Introduction to Udemy Python 3 + Application] 22. Tuple unpacking
[Introduction to Udemy Python3 + Application] 42. for statement, break statement, and continue statement
[Introduction to Udemy Python3 + Application] 39. while statement, continue statement and break statement
[Introduction to Udemy Python3 + Application] 23. How to use tuples
[Introduction to Udemy Python3 + Application] 60. List comprehension notation
[Introduction to Udemy Python 3 + Application] 19. Copy of list
[Introduction to Udemy Python 3 + Application] 38. When judging None
[Introduction to Udemy Python3 + Application] 62. Set comprehension notation
[Introduction to Udemy Python3 + Application] 64. Namespace and Scope
[Introduction to Udemy Python3 + Application] 67. Command line arguments
[Introduction to Udemy Python3 + Application] 9. First, print with print
[Introduction to Udemy Python 3 + Application] 54. What is Docstrings?
[Introduction to Udemy Python3 + Application] 14. Character substitution 15.f-strings
[Introduction to Udemy Python3 + Application] 47. Process the dictionary with a for statement
[Introduction to Udemy Python3 + Application] 35. Comparison operators and logical operators
[Introduction to Udemy Python 3 + Application] 66. Creating your own exceptions
[Introduction to Udemy Python3 + Application] 53. Dictionary of keyword arguments
[Introduction to Udemy Python3 + Application] 27. How to use the dictionary
[Introduction to Udemy Python3 + Application] 30. How to use the set
[Introduction to Udemy Python3 + Application] 52. Tupleization of positional arguments
Python if statement
[Python] if statement
[Introduction to Udemy Python 3 + Application] 36. How to use In and Not
[Introduction to Udemy Python3 + Application] 32.1 When one line becomes long
[Introduction to Udemy Python3 + Application] 50. Positional arguments, keyword arguments, and default arguments
[Introduction to Udemy Python3 + Application] 51. Be careful with default arguments
[Introduction to Udemy Python3 + Application] 49. Function citation and return value declaration
[Introduction to Udemy Python3 + Application] 69. Import of absolute path and relative path
[Introduction to Udemy Python3 + Application] 12. Indexing and slicing of character strings
Introduction to Python language
Introduction to OpenCV (python)-(2)