# lambda

### lambda

lambda functions are nameless function. lambda functions are usually one line functions. lambda functions are usually used as input parameter to map and filter function.

For example:

Make every element of list \[1,2,3,4,5] square

```
list(map(lambda x: x**2,[1,2,3,4,5]))
```

Output:

\[1, 4, 9, 16, 25]

Filter out odd element, only keep even element of a list

```
list(filter(lambda x: x%2==0, [1,2,3,4,5]))
```

It output below:

\[2,4]


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