/*
* 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.block.Block;
import com.facebook.presto.block.BlockBuilder;
import com.facebook.presto.block.BlockCursor;
import com.facebook.presto.operator.GroupByIdBlock;
import com.facebook.presto.tuple.TupleInfo.Type;
import com.facebook.presto.util.array.DoubleBigArray;
import com.facebook.presto.util.array.LongBigArray;
import com.google.common.base.Optional;
import io.airlift.slice.Slice;
import io.airlift.slice.Slices;
import static com.facebook.presto.tuple.TupleInfo.SINGLE_DOUBLE;
import static com.facebook.presto.tuple.TupleInfo.SINGLE_VARBINARY;
import static com.google.common.base.Preconditions.checkState;
import static io.airlift.slice.SizeOf.SIZE_OF_DOUBLE;
import static io.airlift.slice.SizeOf.SIZE_OF_LONG;
public class AverageAggregation
extends SimpleAggregationFunction
{
private final boolean inputIsLong;
public AverageAggregation(Type parameterType)
{
super(SINGLE_DOUBLE, SINGLE_VARBINARY, parameterType);
if (parameterType == Type.FIXED_INT_64) {
this.inputIsLong = true;
}
else if (parameterType == Type.DOUBLE) {
this.inputIsLong = false;
}
else {
throw new IllegalArgumentException("Expected parameter type to be FIXED_INT_64 or DOUBLE, but was " + parameterType);
}
}
@Override
protected GroupedAccumulator createGroupedAccumulator(Optional<Integer> maskChannel, int valueChannel)
{
return new AverageGroupedAccumulator(valueChannel, inputIsLong, maskChannel);
}
public static class AverageGroupedAccumulator
extends SimpleGroupedAccumulator
{
private final boolean inputIsLong;
private final LongBigArray counts;
private final DoubleBigArray sums;
public AverageGroupedAccumulator(int valueChannel, boolean inputIsLong, Optional<Integer> maskChannel)
{
super(valueChannel, SINGLE_DOUBLE, SINGLE_VARBINARY, maskChannel);
this.inputIsLong = inputIsLong;
this.counts = new LongBigArray();
this.sums = new DoubleBigArray();
}
@Override
public long getEstimatedSize()
{
return counts.sizeOf() + sums.sizeOf();
}
@Override
public void processInput(GroupByIdBlock groupIdsBlock, Block valuesBlock, Optional<Block> maskBlock)
{
counts.ensureCapacity(groupIdsBlock.getGroupCount());
sums.ensureCapacity(groupIdsBlock.getGroupCount());
BlockCursor values = valuesBlock.cursor();
BlockCursor masks = null;
if (maskBlock.isPresent()) {
masks = maskBlock.get().cursor();
}
for (int position = 0; position < groupIdsBlock.getPositionCount(); position++) {
checkState(values.advanceNextPosition());
checkState(masks == null || masks.advanceNextPosition());
long groupId = groupIdsBlock.getGroupId(position);
if (!values.isNull() && (masks == null || masks.getBoolean())) {
counts.increment(groupId);
double value;
if (inputIsLong) {
value = values.getLong();
}
else {
value = values.getDouble();
}
sums.add(groupId, value);
}
}
checkState(!values.advanceNextPosition());
}
@Override
public void processIntermediate(GroupByIdBlock groupIdsBlock, Block block)
{
counts.ensureCapacity(groupIdsBlock.getGroupCount());
sums.ensureCapacity(groupIdsBlock.getGroupCount());
BlockCursor intermediateValues = block.cursor();
for (int position = 0; position < groupIdsBlock.getPositionCount(); position++) {
checkState(intermediateValues.advanceNextPosition());
long groupId = groupIdsBlock.getGroupId(position);
Slice value = intermediateValues.getSlice();
long count = value.getLong(0);
counts.add(groupId, count);
double sum = value.getDouble(SIZE_OF_LONG);
sums.add(groupId, sum);
}
checkState(!intermediateValues.advanceNextPosition());
}
@Override
public void evaluateIntermediate(int groupId, BlockBuilder output)
{
long count = counts.get((long) groupId);
double sum = sums.get((long) groupId);
// todo replace this when general fixed with values are supported
Slice value = Slices.allocate(SIZE_OF_LONG + SIZE_OF_DOUBLE);
value.setLong(0, count);
value.setDouble(SIZE_OF_LONG, sum);
output.append(value);
}
@Override
public void evaluateFinal(int groupId, BlockBuilder output)
{
long count = counts.get((long) groupId);
if (count != 0) {
double value = sums.get((long) groupId);
output.append(value / count);
}
else {
output.appendNull();
}
}
}
@Override
protected Accumulator createAccumulator(Optional<Integer> maskChannel, int valueChannel)
{
return new AverageAccumulator(valueChannel, inputIsLong, maskChannel);
}
public static class AverageAccumulator
extends SimpleAccumulator
{
private final boolean inputIsLong;
private long count;
private double sum;
public AverageAccumulator(int valueChannel, boolean inputIsLong, Optional<Integer> maskChannel)
{
super(valueChannel, SINGLE_DOUBLE, SINGLE_VARBINARY, maskChannel);
this.inputIsLong = inputIsLong;
}
@Override
protected void processInput(Block block, Optional<Block> maskBlock)
{
BlockCursor values = block.cursor();
BlockCursor masks = null;
if (maskBlock.isPresent()) {
masks = maskBlock.get().cursor();
}
for (int position = 0; position < block.getPositionCount(); position++) {
checkState(values.advanceNextPosition());
checkState(masks == null || masks.advanceNextPosition());
if (!values.isNull() && (masks == null || masks.getBoolean())) {
count++;
if (inputIsLong) {
sum += values.getLong();
}
else {
sum += values.getDouble();
}
}
}
}
@Override
protected void processIntermediate(Block block)
{
BlockCursor intermediates = block.cursor();
for (int position = 0; position < block.getPositionCount(); position++) {
checkState(intermediates.advanceNextPosition());
Slice value = intermediates.getSlice();
count += value.getLong(0);
sum += value.getDouble(SIZE_OF_LONG);
}
}
@Override
public void evaluateIntermediate(BlockBuilder out)
{
// todo replace this when general fixed with values are supported
Slice value = Slices.allocate(SIZE_OF_LONG + SIZE_OF_DOUBLE);
value.setLong(0, count);
value.setDouble(SIZE_OF_LONG, sum);
out.append(value);
}
@Override
public void evaluateFinal(BlockBuilder out)
{
if (count != 0) {
out.append(sum / count);
}
else {
out.appendNull();
}
}
}
}