public class CompressedSizeEstimatorExact extends CompressedSizeEstimator
Constructor and Description |
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CompressedSizeEstimatorExact(MatrixBlock data,
CompressionSettings compSettings) |
Modifier and Type | Method and Description |
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CompressedSizeInfoColGroup |
estimateCompressedColGroupSize(int[] colIndexes,
int nrUniqueUpperBound)
A method to extract the Compressed Size Info for a given list of columns, This method further limits the
estimated number of unique values, since in some cases the estimated number of uniques is estimated higher than
the number estimated in sub groups of the given colIndexes.
|
CompressedSizeInfoColGroup |
estimateJoinCompressedSize(int[] joined,
CompressedSizeInfoColGroup g1,
CompressedSizeInfoColGroup g2) |
computeCompressedSizeInfos, computeCompressedSizeInfos, computeCompressedSizeInfos, estimateCompressedColGroupSize, estimateCompressedColGroupSize, estimateCompressedColGroupSize, estimateCompressedColGroupSize, estimateJoinCompressedSize, getNumColumns, getNumRows, toString
public CompressedSizeEstimatorExact(MatrixBlock data, CompressionSettings compSettings)
public CompressedSizeInfoColGroup estimateCompressedColGroupSize(int[] colIndexes, int nrUniqueUpperBound)
CompressedSizeEstimator
estimateCompressedColGroupSize
in class CompressedSizeEstimator
colIndexes
- The columns to extract compression information fromnrUniqueUpperBound
- The upper bound of unique elements allowed in the estimate, can be calculated from the
number of unique elements estimated in sub columns multiplied together. This is
flexible in the sense that if the sample is small then this unique can be manually
edited like in CoCodeCostMatrixMult.public CompressedSizeInfoColGroup estimateJoinCompressedSize(int[] joined, CompressedSizeInfoColGroup g1, CompressedSizeInfoColGroup g2)
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