# all

> For the complete documentation index, see [llms.txt](https://kotlin.github.io/dataframe/llms.txt).

Checks if all rows in the [DataFrame](dataframe.html) satisfy the predicate.

API reference: [all](https://kotlin.github.io/dataframe/api-docs/core/org.jetbrains.kotlinx.dataframe.api/all.html)

Returns `Boolean` — `true` if every row satisfies the predicate, `false` otherwise.

```KOTLIN
all { rowCondition }

rowCondition: (DataRow) -> Boolean
```

When called on a [DataColumn](datacolumn.html), checks that all values in the [DataColumn](datacolumn.html) satisfy the predicate.

Related operations: [any](any.html), [filter](filter.html), [single](single.html), [count](count.html).

## Examples

```KOTLIN
df
```

[Embedded content](./resources/notebook_test_all_3.html)

Check if all persons' `age` is greater than 21:

```KOTLIN
df.all { age > 21 }
```

Output:

```TEXT
false
```

Check if all persons have `age` greater or equal to 15:

```KOTLIN
df.all { name.first().isUpperCase() && age >= 15 }
```

Output:

```TEXT
true
```