## FANDOM

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List comprehension provides a concise way of creating lists.

## Generalized Structures Edit

### Basic Edit

##### List Comprehension Edit
```(values) = [(expression) for (value) in (collection)]
```
##### For Loop Edit
```(values) = []
for (value) in (collection):
(values).append((expression))
```

### Filtering Edit

##### List Comprehension Edit
```(values) = [(expression) for (value) in (collection) if (condition)]
```
##### For Loop Edit
```(values) = []
for (value) in (collection):
if (condition):
(values).append((expression))
```

## Examples Edit

### Basic Example Edit

Here is a piece of code that calculates the squares of 0 - 9 NOT using list comprehension.

```squares = []
for x in range(10):
squares.append(x * x)
```

Returns :

```[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
```

Now here is the same code but using list comprehension:

```squares = [x * x for x in range(10)]
```

### Filtering Edit

Here we are calculating the same set of values as above but we are only keeping the even numbers.

```even_squares = [x * x for x in range(10) if x % 2 == 0
```

Returns :

```[0, 4, 16, 36, 64]
```

If you wanted to do the same thing with a for-loop:

```even_squares = []
for x in range(10):
if x % 2 == 0:
even_squares.append(x * x)
```
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