/*
* 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.RegressionState;
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.getRegressionIntercept;
import static com.facebook.presto.operator.aggregation.AggregationUtils.getRegressionSlope;
import static com.facebook.presto.operator.aggregation.AggregationUtils.mergeRegressionState;
import static com.facebook.presto.operator.aggregation.AggregationUtils.updateRegressionState;
import static com.facebook.presto.spi.type.DoubleType.DOUBLE;
@AggregationFunction
public class DoubleRegressionAggregation
{
private DoubleRegressionAggregation() {}
@InputFunction
public static void input(@AggregationState RegressionState state, @SqlType(StandardTypes.DOUBLE) double dependentValue, @SqlType(StandardTypes.DOUBLE) double independentValue)
{
updateRegressionState(state, independentValue, dependentValue);
}
@CombineFunction
public static void combine(@AggregationState RegressionState state, @AggregationState RegressionState otherState)
{
mergeRegressionState(state, otherState);
}
@AggregationFunction("regr_slope")
@OutputFunction(StandardTypes.DOUBLE)
public static void regrSlope(@AggregationState RegressionState state, BlockBuilder out)
{
double result = getRegressionSlope(state);
if (Double.isFinite(result)) {
DOUBLE.writeDouble(out, result);
}
else {
out.appendNull();
}
}
@AggregationFunction("regr_intercept")
@OutputFunction(StandardTypes.DOUBLE)
public static void regrIntercept(@AggregationState RegressionState state, BlockBuilder out)
{
double result = getRegressionIntercept(state);
if (Double.isFinite(result)) {
DOUBLE.writeDouble(out, result);
}
else {
out.appendNull();
}
}
}