# Filter Operator

Filters an array (or map values) by the expression given. Equivalent to doing `map(select(exp))`.

## Filter array

Given a sample.yml file of:

```yaml
- 1
- 2
- 3
```

then

```bash
yq 'filter(. < 3)' sample.yml
```

will output

```yaml
- 1
- 2
```

## Filter map values

Given a sample.yml file of:

```yaml
c:
  things: cool
  frog: yes
d:
  things: hot
  frog: false
```

then

```bash
yq 'filter(.things == "cool")' sample.yml
```

will output

```yaml
- things: cool
  frog: yes
```


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