---
title: RowGroupingProtocol
framework: tabulardata
role: symbol
role_heading: Protocol
path: tabulardata/rowgroupingprotocol
---

# RowGroupingProtocol

A type that represents a collection of row selections that have the same value in a column.

## Declaration

```swift
protocol RowGroupingProtocol : CustomStringConvertible
```

## Topics

### Inspecting a Row Grouping

- [count](tabulardata/rowgroupingprotocol/count.md)

### Transforming a Row Grouping

- [mapGroups(_:)](tabulardata/rowgroupingprotocol/mapgroups(_:).md)

### Splitting a Row Grouping

- [randomSplit(by:)](tabulardata/rowgroupingprotocol/randomsplit(by:).md)
- [randomSplit(by:seed:)](tabulardata/rowgroupingprotocol/randomsplit(by:seed:).md)

### Aggregating a Row Grouping

- [counts()](tabulardata/rowgroupingprotocol/counts().md)
- [counts(order:)](tabulardata/rowgroupingprotocol/counts(order:).md)
- [sums(_:_:order:)](tabulardata/rowgroupingprotocol/sums(_:_:order:).md)
- [sums(_:order:)](tabulardata/rowgroupingprotocol/sums(_:order:).md)
- [means(_:_:order:)](tabulardata/rowgroupingprotocol/means(_:_:order:).md)
- [means(_:order:)](tabulardata/rowgroupingprotocol/means(_:order:).md)
- [minimums(_:_:order:)](tabulardata/rowgroupingprotocol/minimums(_:_:order:).md)
- [minimums(_:order:)](tabulardata/rowgroupingprotocol/minimums(_:order:).md)
- [maximums(_:_:order:)](tabulardata/rowgroupingprotocol/maximums(_:_:order:).md)
- [maximums(_:order:)](tabulardata/rowgroupingprotocol/maximums(_:order:).md)
- [aggregated(on:into:transform:)](tabulardata/rowgroupingprotocol/aggregated(on:into:transform:).md)
- [aggregated(on:naming:transform:)](tabulardata/rowgroupingprotocol/aggregated(on:naming:transform:).md)

### Flattening a Row Grouping

- [ungrouped()](tabulardata/rowgroupingprotocol/ungrouped().md)

### Summarizing a Row Grouping

- [summary()](tabulardata/rowgroupingprotocol/summary().md)
- [summary(of:)](tabulardata/rowgroupingprotocol/summary(of:).md)
- [GroupSummaries](tabulardata/groupsummaries.md)

### Instance Methods

- [filter(_:)](tabulardata/rowgroupingprotocol/filter(_:).md)
- [quantiles(_:_:quantile:order:)](tabulardata/rowgroupingprotocol/quantiles(_:_:quantile:order:).md)
- [quantiles(_:quantile:order:)](tabulardata/rowgroupingprotocol/quantiles(_:quantile:order:).md)

### Subscripts

- [subscript(_:)](tabulardata/rowgroupingprotocol/subscript(_:).md)

## Relationships

### Inherits From

- [CustomStringConvertible](swift/customstringconvertible.md)

### Conforming Types

- [RowGrouping](tabulardata/rowgrouping.md)

## See Also

### Grouping Rows

- [RowGrouping](tabulardata/rowgrouping.md)
- [grouped(by:)](tabulardata/dataframe/grouped(by:).md)