Aggregation (cudfjni 21.06.1 API)

java.lang.Object
- ai.rapids.cudf.Aggregation

Direct Known Subclasses:

Aggregation.AllAggregation, Aggregation.AnyAggregation, Aggregation.ArgMaxAggregation, Aggregation.ArgMinAggregation, Aggregation.CollectListAggregation, Aggregation.CountAggregation, Aggregation.LagAggregation, Aggregation.LeadAggregation, Aggregation.MaxAggregation, Aggregation.MeanAggregation, Aggregation.MedianAggregation, Aggregation.MinAggregation, Aggregation.NthAggregation, Aggregation.NuniqueAggregation, Aggregation.ProductAggregation, Aggregation.RowNumberAggregation, Aggregation.StandardDeviationAggregation, Aggregation.SumAggregation, Aggregation.SumOfSquaresAggregation, Aggregation.VarianceAggregation, AggregationOnColumn
```
public abstract class Aggregation
extends Object
```
Represents an aggregation operation. Please note that not all aggregations work, or even make since in all types of aggregation operations.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`Aggregation.AllAggregation`
`static class`	`Aggregation.AnyAggregation`
`static class`	`Aggregation.ArgMaxAggregation`
`static class`	`Aggregation.ArgMinAggregation`
`static class`	`Aggregation.CollectListAggregation`
`static class`	`Aggregation.CountAggregation`
`static class`	`Aggregation.LagAggregation`
`static class`	`Aggregation.LeadAggregation`
`static class`	`Aggregation.MaxAggregation`
`static class`	`Aggregation.MeanAggregation`
`static class`	`Aggregation.MedianAggregation`
`static class`	`Aggregation.MinAggregation`
`static class`	`Aggregation.NthAggregation`
`static class`	`Aggregation.NuniqueAggregation`
`static class`	`Aggregation.ProductAggregation`
`static class`	`Aggregation.RowNumberAggregation`
`static class`	`Aggregation.StandardDeviationAggregation`
`static class`	`Aggregation.SumAggregation`
`static class`	`Aggregation.SumOfSquaresAggregation`
`static class`	`Aggregation.VarianceAggregation`

Field Summary

Fields
Modifier and Type Field and Description

protected ai.rapids.cudf.Aggregation.Kind kind

Fields
Modifier and Type	Field and Description
`protected ai.rapids.cudf.Aggregation.Kind`	`kind`

Constructor Summary

Constructors
Modifier Constructor and Description

protected Aggregation(ai.rapids.cudf.Aggregation.Kind kind)

Constructors
Modifier	Constructor and Description
`protected`	`Aggregation(ai.rapids.cudf.Aggregation.Kind kind)`

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`static Aggregation.AllAggregation`	`all()` All reduction.
`static Aggregation.AnyAggregation`	`any()` Any reduction.
`static Aggregation.ArgMaxAggregation`	`argMax()` Index of max element.
`static Aggregation.ArgMinAggregation`	`argMin()` Index of min element.
`static Aggregation.CollectListAggregation`	`collectList()` Collect the values into a list.
`static Aggregation.CollectListAggregation`	`collectList(NullPolicy nullPolicy)` Collect the values into a list.
`static ai.rapids.cudf.Aggregation.CollectSetAggregation`	`collectSet()` Collect the values into a set.
`static ai.rapids.cudf.Aggregation.CollectSetAggregation`	`collectSet(NullPolicy nullPolicy, NullEquality nullEquality, NaNEquality nanEquality)` Collect the values into a set.
`static Aggregation.CountAggregation`	`count()` Count number of valid, a.k.a.
`static Aggregation.CountAggregation`	`count(NullPolicy nullPolicy)` Count number of elements.
`abstract boolean`	`equals(Object other)`
`abstract int`	`hashCode()`
`static Aggregation.LagAggregation`	`lag(int offset)` In a rolling window return the value offset entries behind or null if it is outside of the window.
`static Aggregation.LagAggregation`	`lag(int offset, ColumnVector defaultOutput)` In a rolling window return the value offset entries behind or the corresponding value from defaultOutput if it is outside of the window.
`static Aggregation.LeadAggregation`	`lead(int offset)` In a rolling window return the value offset entries ahead or null if it is outside of the window.
`static Aggregation.LeadAggregation`	`lead(int offset, ColumnVector defaultOutput)` In a rolling window return the value offset entries ahead or the corresponding value from defaultOutput if it is outside of the window.
`static Aggregation.MaxAggregation`	`max()` Max reduction.
`static Aggregation.MeanAggregation`	`mean()` Arithmetic mean reduction.
`static Aggregation.MedianAggregation`	`median()` Median reduction.
`static Aggregation.MinAggregation`	`min()` Min reduction.
`static Aggregation.NthAggregation`	`nth(int offset)` Get the nth, non-null, element in a group.
`static Aggregation.NthAggregation`	`nth(int offset, NullPolicy nullPolicy)` Get the nth element in a group.
`static Aggregation.NuniqueAggregation`	`nunique()` Number of unique, non-null, elements.
`static Aggregation.NuniqueAggregation`	`nunique(NullPolicy nullPolicy)` Number of unique elements.
`<T extends Aggregation> AggregationOnColumn<T>`	`onColumn(int columnIndex)` Add a column to the Aggregation so it can be used on a specific column of data.
`static Aggregation.ProductAggregation`	`product()` Product reduction.
`static ai.rapids.cudf.Aggregation.QuantileAggregation`	`quantile(double... quantiles)` Aggregate to compute the specified quantiles.
`static ai.rapids.cudf.Aggregation.QuantileAggregation`	`quantile(QuantileMethod method, double... quantiles)` Aggregate to compute various quantiles.
`static Aggregation.RowNumberAggregation`	`rowNumber()` Get the row number, only makes since for a window operations.
`static Aggregation.StandardDeviationAggregation`	`standardDeviation()` Standard deviation aggregation with 1 as the delta degrees of freedom.
`static Aggregation.StandardDeviationAggregation`	`standardDeviation(int ddof)` Standard deviation aggregation.
`static Aggregation.SumAggregation`	`sum()` Sum reduction.
`static Aggregation.SumOfSquaresAggregation`	`sumOfSquares()` Sum of squares reduction.
`static Aggregation.VarianceAggregation`	`variance()` Variance aggregation with 1 as the delta degrees of freedom.
`static Aggregation.VarianceAggregation`	`variance(int ddof)` Variance aggregation.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - kind
```
protected final ai.rapids.cudf.Aggregation.Kind kind
```
- Constructor Detail
  - Aggregation
```
protected Aggregation(ai.rapids.cudf.Aggregation.Kind kind)
```
- Method Detail
  - onColumn
```
public <T extends Aggregation> AggregationOnColumn<T> onColumn(int columnIndex)
```
    Add a column to the Aggregation so it can be used on a specific column of data.
    
    Parameters:
    
    columnIndex - the index of the column to operate on.
  - hashCode
```
public abstract int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - equals
```
public abstract boolean equals(Object other)
```
    Overrides:
    
    equals in class Object
  - sum
```
public static Aggregation.SumAggregation sum()
```
    Sum reduction.
  - product
```
public static Aggregation.ProductAggregation product()
```
    Product reduction.
  - min
```
public static Aggregation.MinAggregation min()
```
    Min reduction.
  - max
```
public static Aggregation.MaxAggregation max()
```
    Max reduction.
  - count
```
public static Aggregation.CountAggregation count()
```
    Count number of valid, a.k.a. non-null, elements.
  - count
```
public static Aggregation.CountAggregation count(NullPolicy nullPolicy)
```
    Count number of elements.
    
    Parameters:
    
    nullPolicy - INCLUDE if nulls should be counted. EXCLUDE if only non-null values should be counted.
  - any
```
public static Aggregation.AnyAggregation any()
```
    Any reduction. Produces a true or 1, depending on the output type, if any of the elements in the range are true or non-zero, otherwise produces a false or 0. Null values are skipped.
  - all
```
public static Aggregation.AllAggregation all()
```
    All reduction. Produces true or 1, depending on the output type, if all of the elements in the range are true or non-zero, otherwise produces a false or 0. Null values are skipped.
  - sumOfSquares
```
public static Aggregation.SumOfSquaresAggregation sumOfSquares()
```
    Sum of squares reduction.
  - mean
```
public static Aggregation.MeanAggregation mean()
```
    Arithmetic mean reduction.
  - variance
```
public static Aggregation.VarianceAggregation variance()
```
    Variance aggregation with 1 as the delta degrees of freedom.
  - variance
```
public static Aggregation.VarianceAggregation variance(int ddof)
```
    Variance aggregation.
    
    Parameters:
    
    ddof - delta degrees of freedom. The divisor used in calculation of variance is N - ddof, where N is the population size.
  - standardDeviation
```
public static Aggregation.StandardDeviationAggregation standardDeviation()
```
    Standard deviation aggregation with 1 as the delta degrees of freedom.
  - standardDeviation
```
public static Aggregation.StandardDeviationAggregation standardDeviation(int ddof)
```
    Standard deviation aggregation.
    
    Parameters:
    
    ddof - delta degrees of freedom. The divisor used in calculation of std is N - ddof, where N is the population size.
  - median
```
public static Aggregation.MedianAggregation median()
```
    Median reduction.
  - quantile
```
public static ai.rapids.cudf.Aggregation.QuantileAggregation quantile(double... quantiles)
```
    Aggregate to compute the specified quantiles. Uses linear interpolation by default.
  - quantile
```
public static ai.rapids.cudf.Aggregation.QuantileAggregation quantile(QuantileMethod method,
                                                                      double... quantiles)
```
    Aggregate to compute various quantiles.
  - argMax
```
public static Aggregation.ArgMaxAggregation argMax()
```
    Index of max element. Please note that when using this aggregation with a group by if the data is not already sorted by the grouping keys it may be automatically sorted prior to doing the aggregation. This would result in an index into the sorted data being returned.
  - argMin
```
public static Aggregation.ArgMinAggregation argMin()
```
    Index of min element. Please note that when using this aggregation with a group by if the data is not already sorted by the grouping keys it may be automatically sorted prior to doing the aggregation. This would result in an index into the sorted data being returned.
  - nunique
```
public static Aggregation.NuniqueAggregation nunique()
```
    Number of unique, non-null, elements.
  - nunique
```
public static Aggregation.NuniqueAggregation nunique(NullPolicy nullPolicy)
```
    Number of unique elements.
    
    Parameters:
    
    nullPolicy - INCLUDE if nulls should be counted else EXCLUDE. If nulls are counted they compare as equal so multiple null values in a range would all only increase the count by 1.
  - nth
```
public static Aggregation.NthAggregation nth(int offset)
```
    Get the nth, non-null, element in a group.
    
    Parameters:
    
    offset - the offset to look at. Negative numbers go from the end of the group. Any value outside of the group range results in a null.
  - nth
```
public static Aggregation.NthAggregation nth(int offset,
                                             NullPolicy nullPolicy)
```
    Get the nth element in a group.
    
    Parameters:
    
    offset - the offset to look at. Negative numbers go from the end of the group. Any value outside of the group range results in a null.
    
    nullPolicy - INCLUDE if nulls should be included in the aggregation or EXCLUDE if they should be skipped.
  - rowNumber
```
public static Aggregation.RowNumberAggregation rowNumber()
```
    Get the row number, only makes since for a window operations.
  - collectList
```
public static Aggregation.CollectListAggregation collectList()
```
    Collect the values into a list. Nulls will be skipped.
  - collectList
```
public static Aggregation.CollectListAggregation collectList(NullPolicy nullPolicy)
```
    Collect the values into a list.
    
    Parameters:
    
    nullPolicy - Indicates whether to include/exclude nulls during collection.
  - collectSet
```
public static ai.rapids.cudf.Aggregation.CollectSetAggregation collectSet()
```
    Collect the values into a set. All null values will be excluded, and all nan values are regarded as unique instances.
  - collectSet
```
public static ai.rapids.cudf.Aggregation.CollectSetAggregation collectSet(NullPolicy nullPolicy,
                                                                          NullEquality nullEquality,
                                                                          NaNEquality nanEquality)
```
    Collect the values into a set.
    
    Parameters:
    
    nullPolicy - Indicates whether to include/exclude nulls during collection.
    
    nullEquality - Flag to specify whether null entries within each list should be considered equal.
    
    nanEquality - Flag to specify whether NaN values in floating point column should be considered equal.
  - lead
```
public static Aggregation.LeadAggregation lead(int offset)
```
    In a rolling window return the value offset entries ahead or null if it is outside of the window.
  - lead
```
public static Aggregation.LeadAggregation lead(int offset,
                                               ColumnVector defaultOutput)
```
    In a rolling window return the value offset entries ahead or the corresponding value from defaultOutput if it is outside of the window. Note that this does not take any ownership of defaultOutput and the caller mush ensure that defaultOutput remains valid during the life time of this aggregation operation.
  - lag
```
public static Aggregation.LagAggregation lag(int offset)
```
    In a rolling window return the value offset entries behind or null if it is outside of the window.
  - lag
```
public static Aggregation.LagAggregation lag(int offset,
                                             ColumnVector defaultOutput)
```
    In a rolling window return the value offset entries behind or the corresponding value from defaultOutput if it is outside of the window. Note that this does not take any ownership of defaultOutput and the caller mush ensure that defaultOutput remains valid during the life time of this aggregation operation.

Class Aggregation

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

kind

Constructor Detail

Aggregation

Method Detail

onColumn

hashCode

equals

sum

product

min

max

count

count

any

all

sumOfSquares

mean

variance

variance

standardDeviation

standardDeviation

median

quantile

quantile

argMax

argMin

nunique

nunique

nth

nth

rowNumber

collectList

collectList

collectSet

collectSet

lead

lead

lag

lag