Package org.apache.sysds.runtime.compress.bitmap

Class Bitmap

java.lang.Object

org.apache.sysds.runtime.compress.bitmap.ABitmap

org.apache.sysds.runtime.compress.bitmap.Bitmap

public final class Bitmap
extends ABitmap

Uncompressed representation of one or more columns in bitmap format.

Method Summary

Modifier and Type	Method	Description
int	getNumColumns()	Get the number of columns encoded in this bitmap
int	getNumNonZerosInOffset(int idx)	Get the number of non zeros in a specific offset's tuple value.
int	getNumValues()	Obtain number of distinct value groups in the column.
double[]	getValues()	Get all values without unnecessary allocations and copies.

Methods inherited from class org.apache.sysds.runtime.compress.bitmap.ABitmap

containsZero, getNumOffsets, getNumOffsets, getNumZeros, getOffsetList, getOffsetsList, toString

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

getValues

public final double[] getValues()

Get all values without unnecessary allocations and copies.

Returns:

Dictionary of distinct values

getNumNonZerosInOffset

public final int getNumNonZerosInOffset(int idx)

Description copied from class: ABitmap

Get the number of non zeros in a specific offset's tuple value.

Specified by:

getNumNonZerosInOffset in class ABitmap

Parameters:

idx - The offset index to look at.

Returns:

The nnz in the tuple.

getNumValues

public final int getNumValues()

Description copied from class: ABitmap

Obtain number of distinct value groups in the column. this number is also the number of bitmaps, since there is one bitmap per value

Specified by:

getNumValues in class ABitmap

Returns:

number of distinct value groups in the column;

getNumColumns

public int getNumColumns()

Description copied from class: ABitmap

Get the number of columns encoded in this bitmap

Specified by:

getNumColumns in class ABitmap

Returns:

The column count