Nesting ternary operators in python

The ternary operator puts together simple if-else statements on one line, making them easier to read.

if-else statement

For example, if you want to display foo as the value when v is greater than 10, and bar otherwise, write it in an if-else statement and write it in 4 lines.

if-4 lines when written in else statement

In [22]: for v in range(-5, 15):   
    ...:     if v > 10:               
    ...:         p = 'foo'            
    ...:     else:                    
    ...:         p = 'bar'            
    ...:     print(v, p)              
    ...:                              
-5 bar                                
-4 bar                                
-3 bar                                
-2 bar                                
-1 bar                                
0 bar                                 
1 bar                                 
2 bar                                 
3 bar                                 
4 bar                                 
5 bar                                 
6 bar                                 
7 bar                                 
8 bar                                 
9 bar                                 
10 bar                                
11 foo                                
12 foo                                
13 foo                                
14 foo                                

Ternary operator

The grammar of the ternary operator is

(variable) = (Value when the condition is True) if (conditions) else (conditionsがFalseのときの値) 

The ternary operator can be written in one line.

One line when written with a ternary operator

In [26]: for v in range(-5, 15):
    ...:     p = 'foo' if v > 10 else 'bar'
    ...:     print(v, p)
-5 bar
-4 bar
-3 bar
-2 bar
-1 bar
0 bar
1 bar
2 bar
3 bar
4 bar
5 bar
6 bar
7 bar
8 bar
9 bar
10 bar
11 foo
12 foo
13 foo
14 foo

** Here, the if-else statements between the for-print statements are summarized by the ternary operator. ** **

Nest

if-elif-else statement

When adding one condition and outputting'foobar' if it is less than 0, add ʻelif`.

This will output "'foo' if it is greater than 10,'foobar' if it is less than 0, and'bar' otherwise."

if-Two or more else statement conditions

In [36]: for v in range(-5, 15, 1):
    ...:     if v > 10:
    ...:         p = 'foo'
    ...:     elif v < 0:
    ...:         p = 'foobar'
    ...:     else:
    ...:         p = 'bar'
    ...:     print(v, p)
    ...:
-5 foobar
-4 foobar
-3 foobar
-2 foobar
-1 foobar
0 bar
1 bar
2 bar
3 bar
4 bar
5 bar
6 bar
7 bar
8 bar
9 bar
10 bar
11 foo
12 foo
13 foo
14 foo

Nesting ternary operators

The grammar for nesting ternary operators is

(variable) = (Value when the condition is True) if (conditions) else (conditionsがFalseのときの値) if (conditions) else (conditionsがFalseのときの値) ...if-()-else-()Connect infinitely

Nested ternary operator

In [38]: for v in range(-5, 15, 1):
    ...:     p = 'foo' if v > 10 else 'foobar' if v < 0 else 'bar'
    ...:     print(v, p)
-5 foobar
-4 foobar
-3 foobar
-2 foobar
-1 foobar
0 bar
1 bar
2 bar
3 bar
4 bar
5 bar
6 bar
7 bar
8 bar
9 bar
10 bar
11 foo
12 foo
13 foo
14 foo

reference

Qiita --Ternary Operator (Python)