python Python中的基本函数编程

Posted 2021-05-09

### Lambda

Syntax: ```lambda arguments: expression```

__Example__
```
# Regular way of creating a function
def add(x, y):
    return x+y
    
add(3, 4) # return 7
    
# We can shorten function creation by using lambda
# lambda will return a function object
add = lambda x, y: x + y

add(3, 4) # return 7
```

### Map
Syntax: ```map(function_object, iterable1, iterable2, ...)```

__Example__
```
def square(x):
    return x*x
    
list(map(square, [1,2,3,4])) # return [1, 4, 9, 16]

# We can shorten the procedure by using lambda
list(map(lambda x: x*x, [1,2,3,4]))
```

### Filter