ReductionAggregation (cudfjni 24.12.0 API)

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

public final class ReductionAggregation
extends Object

An aggregation that can be used for a reduce.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static ReductionAggregation`	`all()` All reduction.
`static ReductionAggregation`	`any()` Any reduction.
`static ReductionAggregation`	`collectList()`
`static ReductionAggregation`	`collectList(NullPolicy nullPolicy)` Collect the values into a list.
`static ReductionAggregation`	`collectSet()` Collect the values into a set.
`static ReductionAggregation`	`collectSet(NullPolicy nullPolicy, NullEquality nullEquality, NaNEquality nanEquality)` Collect the values into a set.
`static ReductionAggregation`	`createTDigest(int delta)` tDigest reduction.
`boolean`	`equals(Object other)`
`int`	`hashCode()`
`static ReductionAggregation`	`histogram()` Create HistogramAggregation, computing the frequencies for each unique row.
`static ReductionAggregation`	`max()` Max Aggregation
`static ReductionAggregation`	`mean()` Arithmetic mean reduction.
`static ReductionAggregation`	`median()` Median reduction.
`static ReductionAggregation`	`mergeHistogram()` Create MergeHistogramAggregation, to merge multiple histograms.
`static ReductionAggregation`	`mergeLists()` Merge the partial lists produced by multiple CollectListAggregations.
`static ReductionAggregation`	`mergeSets()` Merge the partial sets produced by multiple CollectSetAggregations.
`static ReductionAggregation`	`mergeSets(NullEquality nullEquality, NaNEquality nanEquality)` Merge the partial sets produced by multiple CollectSetAggregations.
`static ReductionAggregation`	`mergeTDigest(int delta)` tDigest merge reduction.
`static ReductionAggregation`	`min()` Min Aggregation
`static ReductionAggregation`	`nth(int offset)` Get the nth, non-null, element in a group.
`static ReductionAggregation`	`nth(int offset, NullPolicy nullPolicy)` Get the nth element in a group.
`static ReductionAggregation`	`nunique()` Number of unique, non-null, elements.
`static ReductionAggregation`	`nunique(NullPolicy nullPolicy)` Number of unique elements.
`static ReductionAggregation`	`product()` Product Aggregation.
`static ReductionAggregation`	`quantile(double... quantiles)` Aggregate to compute the specified quantiles.
`static ReductionAggregation`	`quantile(QuantileMethod method, double... quantiles)` Aggregate to compute various quantiles.
`static ReductionAggregation`	`standardDeviation()` Standard deviation aggregation with 1 as the delta degrees of freedom.
`static ReductionAggregation`	`standardDeviation(int ddof)` Standard deviation aggregation.
`static ReductionAggregation`	`sum()` Sum Aggregation
`static ReductionAggregation`	`sumOfSquares()` Sum of squares reduction.
`static ReductionAggregation`	`variance()` Variance aggregation with 1 as the delta degrees of freedom.
`static ReductionAggregation`	`variance(int ddof)` Variance aggregation.

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

- Method Detail
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - equals
```
public boolean equals(Object other)
```
    Overrides:
    
    equals in class Object
  - sum
```
public static ReductionAggregation sum()
```
    Sum Aggregation
  - product
```
public static ReductionAggregation product()
```
    Product Aggregation.
  - min
```
public static ReductionAggregation min()
```
    Min Aggregation
  - max
```
public static ReductionAggregation max()
```
    Max Aggregation
  - any
```
public static ReductionAggregation 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 ReductionAggregation 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 ReductionAggregation sumOfSquares()
```
    Sum of squares reduction.
  - mean
```
public static ReductionAggregation mean()
```
    Arithmetic mean reduction.
  - variance
```
public static ReductionAggregation variance()
```
    Variance aggregation with 1 as the delta degrees of freedom.
  - variance
```
public static ReductionAggregation 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 ReductionAggregation standardDeviation()
```
    Standard deviation aggregation with 1 as the delta degrees of freedom.
  - standardDeviation
```
public static ReductionAggregation 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 ReductionAggregation median()
```
    Median reduction.
  - quantile
```
public static ReductionAggregation quantile(double... quantiles)
```
    Aggregate to compute the specified quantiles. Uses linear interpolation by default.
  - quantile
```
public static ReductionAggregation quantile(QuantileMethod method,
                                            double... quantiles)
```
    Aggregate to compute various quantiles.
  - nunique
```
public static ReductionAggregation nunique()
```
    Number of unique, non-null, elements.
  - nunique
```
public static ReductionAggregation 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 ReductionAggregation 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 ReductionAggregation 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.
  - createTDigest
```
public static ReductionAggregation createTDigest(int delta)
```
    tDigest reduction.
  - mergeTDigest
```
public static ReductionAggregation mergeTDigest(int delta)
```
    tDigest merge reduction.
  - collectList
```
public static ReductionAggregation collectList()
```
  - collectList
```
public static ReductionAggregation collectList(NullPolicy nullPolicy)
```
    Collect the values into a list.
    
    Parameters:
    
    nullPolicy - Indicates whether to include/exclude nulls during collection.
  - collectSet
```
public static ReductionAggregation 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 ReductionAggregation 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.
  - mergeLists
```
public static ReductionAggregation mergeLists()
```
    Merge the partial lists produced by multiple CollectListAggregations. NOTICE: The partial lists to be merged should NOT include any null list element (but can include null list entries).
  - mergeSets
```
public static ReductionAggregation mergeSets()
```
    Merge the partial sets produced by multiple CollectSetAggregations. Each null/NaN value will be regarded as a unique instance.
  - mergeSets
```
public static ReductionAggregation mergeSets(NullEquality nullEquality,
                                             NaNEquality nanEquality)
```
    Merge the partial sets produced by multiple CollectSetAggregations.
    
    Parameters:
    
    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.
  - histogram
```
public static ReductionAggregation histogram()
```
    Create HistogramAggregation, computing the frequencies for each unique row.
    
    Returns:
    
    A structs column in which the first child stores unique rows from the input and the second child stores their corresponding frequencies.
  - mergeHistogram
```
public static ReductionAggregation mergeHistogram()
```
    Create MergeHistogramAggregation, to merge multiple histograms.
    
    Returns:
    
    A new histogram in which the frequencies of the unique rows are sum up.

Class ReductionAggregation

Method Summary

Methods inherited from class java.lang.Object

Method Detail

hashCode

equals

sum

product

min

max

any

all

sumOfSquares

mean

variance

variance

standardDeviation

standardDeviation

median

quantile

quantile

nunique

nunique

nth

nth

createTDigest

mergeTDigest

collectList

collectList

collectSet

collectSet

mergeLists

mergeSets

mergeSets

histogram

mergeHistogram