/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.facebook.presto.operator.aggregation;
import com.facebook.presto.operator.aggregation.state.CovarianceState;
import com.facebook.presto.spi.block.BlockBuilder;
import com.facebook.presto.spi.function.AggregationFunction;
import com.facebook.presto.spi.function.AggregationState;
import com.facebook.presto.spi.function.CombineFunction;
import com.facebook.presto.spi.function.InputFunction;
import com.facebook.presto.spi.function.OutputFunction;
import com.facebook.presto.spi.function.SqlType;
import com.facebook.presto.spi.type.StandardTypes;
import static com.facebook.presto.operator.aggregation.AggregationUtils.getCovariancePopulation;
import static com.facebook.presto.operator.aggregation.AggregationUtils.getCovarianceSample;
import static com.facebook.presto.spi.type.RealType.REAL;
import static java.lang.Float.intBitsToFloat;
@AggregationFunction
public class RealCovarianceAggregation
{
private RealCovarianceAggregation() {}
@InputFunction
public static void input(@AggregationState CovarianceState state, @SqlType(StandardTypes.REAL) long dependentValue, @SqlType(StandardTypes.REAL) long independentValue)
{
DoubleCovarianceAggregation.input(state, intBitsToFloat((int) dependentValue), intBitsToFloat((int) independentValue));
}
@CombineFunction
public static void combine(@AggregationState CovarianceState state, @AggregationState CovarianceState otherState)
{
DoubleCovarianceAggregation.combine(state, otherState);
}
@AggregationFunction("covar_samp")
@OutputFunction(StandardTypes.REAL)
public static void covarSamp(@AggregationState CovarianceState state, BlockBuilder out)
{
if (state.getCount() <= 1) {
out.appendNull();
}
else {
double result = getCovarianceSample(state);
REAL.writeLong(out, Float.floatToRawIntBits((float) result));
}
}
@AggregationFunction("covar_pop")
@OutputFunction(StandardTypes.REAL)
public static void covarPop(@AggregationState CovarianceState state, BlockBuilder out)
{
if (state.getCount() == 0) {
out.appendNull();
}
else {
double result = getCovariancePopulation(state);
REAL.writeLong(out, Float.floatToRawIntBits((float) result));
}
}
}