Package org.apache.cassandra.utils
Class HistogramBuilder
- java.lang.Object
-
- org.apache.cassandra.utils.HistogramBuilder
-
public class HistogramBuilder extends java.lang.Object
Simple class for constructing an EsimtatedHistogram from a set of predetermined values
-
-
Field Summary
Fields Modifier and Type Field Description static long[]
EMPTY_LONG_ARRAY
static long[]
ZERO
-
Constructor Summary
Constructors Constructor Description HistogramBuilder()
HistogramBuilder(long[] values)
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description void
add(long value)
EstimatedHistogram
buildWithStdevRangesAroundMean()
EstimatedHistogram
buildWithStdevRangesAroundMean(int maxdevs)
Calculate the min, mean, max and standard deviation of the items in the builder, and generate an EstimatedHistogram with uptomaxdev
stdev size ranges either side of the mean, until min/max are hit; if either min/max are not reached a further range is inserted at the relevant ends.
-
-
-
Method Detail
-
add
public void add(long value)
-
buildWithStdevRangesAroundMean
public EstimatedHistogram buildWithStdevRangesAroundMean()
- Returns:
- buildWithStdevRangesAroundMean(3)
-
buildWithStdevRangesAroundMean
public EstimatedHistogram buildWithStdevRangesAroundMean(int maxdevs)
Calculate the min, mean, max and standard deviation of the items in the builder, and generate an EstimatedHistogram with uptomaxdev
stdev size ranges either side of the mean, until min/max are hit; if either min/max are not reached a further range is inserted at the relevant ends. e.g., with amaxdevs
of 3, there may be up to 8 ranges (between 9 boundaries, the middle being the mean); the middle 6 will have the same size (stdev) with the outermost two stretching out to min and max.- Parameters:
maxdevs
-- Returns:
-
-