/*
* 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.ml;
import com.facebook.presto.ml.type.RegressorType;
import com.facebook.presto.spi.block.Block;
import com.facebook.presto.spi.block.BlockBuilder;
import com.facebook.presto.spi.block.BlockBuilderStatus;
import com.facebook.presto.spi.block.InterleavedBlockBuilder;
import com.facebook.presto.spi.function.ScalarFunction;
import com.facebook.presto.spi.function.SqlType;
import com.facebook.presto.spi.type.BigintType;
import com.facebook.presto.spi.type.DoubleType;
import com.facebook.presto.spi.type.StandardTypes;
import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
import com.google.common.collect.ImmutableList;
import com.google.common.hash.HashCode;
import io.airlift.slice.Slice;
import io.airlift.slice.Slices;
import static com.facebook.presto.ml.type.ClassifierType.BIGINT_CLASSIFIER;
import static com.facebook.presto.ml.type.ClassifierType.VARCHAR_CLASSIFIER;
import static com.facebook.presto.ml.type.RegressorType.REGRESSOR;
import static com.google.common.base.Preconditions.checkArgument;
public final class MLFunctions
{
private static final Cache<HashCode, Model> MODEL_CACHE = CacheBuilder.newBuilder().maximumSize(5).build();
private static final String MAP_BIGINT_DOUBLE = "map(bigint,double)";
private MLFunctions()
{
}
@ScalarFunction("classify")
@SqlType(StandardTypes.VARCHAR)
public static Slice varcharClassify(@SqlType(MAP_BIGINT_DOUBLE) Block featuresMap, @SqlType("Classifier<varchar>") Slice modelSlice)
{
FeatureVector features = ModelUtils.toFeatures(featuresMap);
Model model = getOrLoadModel(modelSlice);
checkArgument(model.getType().equals(VARCHAR_CLASSIFIER), "model is not a classifier<varchar>");
Classifier<String> varcharClassifier = (Classifier) model;
return Slices.utf8Slice(varcharClassifier.classify(features));
}
@ScalarFunction
@SqlType(StandardTypes.BIGINT)
public static long classify(@SqlType(MAP_BIGINT_DOUBLE) Block featuresMap, @SqlType("Classifier<bigint>") Slice modelSlice)
{
FeatureVector features = ModelUtils.toFeatures(featuresMap);
Model model = getOrLoadModel(modelSlice);
checkArgument(model.getType().equals(BIGINT_CLASSIFIER), "model is not a classifier<bigint>");
Classifier<Integer> classifier = (Classifier) model;
return classifier.classify(features);
}
@ScalarFunction
@SqlType(StandardTypes.DOUBLE)
public static double regress(@SqlType(MAP_BIGINT_DOUBLE) Block featuresMap, @SqlType(RegressorType.NAME) Slice modelSlice)
{
FeatureVector features = ModelUtils.toFeatures(featuresMap);
Model model = getOrLoadModel(modelSlice);
checkArgument(model.getType().equals(REGRESSOR), "model is not a regressor");
Regressor regressor = (Regressor) model;
return regressor.regress(features);
}
private static Model getOrLoadModel(Slice slice)
{
HashCode modelHash = ModelUtils.modelHash(slice);
Model model = MODEL_CACHE.getIfPresent(modelHash);
if (model == null) {
model = ModelUtils.deserialize(slice);
MODEL_CACHE.put(modelHash, model);
}
return model;
}
@ScalarFunction
@SqlType(MAP_BIGINT_DOUBLE)
public static Block features(@SqlType(StandardTypes.DOUBLE) double f1)
{
return featuresHelper(f1);
}
@ScalarFunction
@SqlType(MAP_BIGINT_DOUBLE)
public static Block features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2)
{
return featuresHelper(f1, f2);
}
@ScalarFunction
@SqlType(MAP_BIGINT_DOUBLE)
public static Block features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3)
{
return featuresHelper(f1, f2, f3);
}
@ScalarFunction
@SqlType(MAP_BIGINT_DOUBLE)
public static Block features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3, @SqlType(StandardTypes.DOUBLE) double f4)
{
return featuresHelper(f1, f2, f3, f4);
}
@ScalarFunction
@SqlType(MAP_BIGINT_DOUBLE)
public static Block features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3, @SqlType(StandardTypes.DOUBLE) double f4, @SqlType(StandardTypes.DOUBLE) double f5)
{
return featuresHelper(f1, f2, f3, f4, f5);
}
@ScalarFunction
@SqlType(MAP_BIGINT_DOUBLE)
public static Block features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3, @SqlType(StandardTypes.DOUBLE) double f4, @SqlType(StandardTypes.DOUBLE) double f5, @SqlType(StandardTypes.DOUBLE) double f6)
{
return featuresHelper(f1, f2, f3, f4, f5, f6);
}
@ScalarFunction
@SqlType(MAP_BIGINT_DOUBLE)
public static Block features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3, @SqlType(StandardTypes.DOUBLE) double f4, @SqlType(StandardTypes.DOUBLE) double f5, @SqlType(StandardTypes.DOUBLE) double f6, @SqlType(StandardTypes.DOUBLE) double f7)
{
return featuresHelper(f1, f2, f3, f4, f5, f6, f7);
}
@ScalarFunction
@SqlType(MAP_BIGINT_DOUBLE)
public static Block features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3, @SqlType(StandardTypes.DOUBLE) double f4, @SqlType(StandardTypes.DOUBLE) double f5, @SqlType(StandardTypes.DOUBLE) double f6, @SqlType(StandardTypes.DOUBLE) double f7, @SqlType(StandardTypes.DOUBLE) double f8)
{
return featuresHelper(f1, f2, f3, f4, f5, f6, f7, f8);
}
@ScalarFunction
@SqlType(MAP_BIGINT_DOUBLE)
public static Block features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3, @SqlType(StandardTypes.DOUBLE) double f4, @SqlType(StandardTypes.DOUBLE) double f5, @SqlType(StandardTypes.DOUBLE) double f6, @SqlType(StandardTypes.DOUBLE) double f7, @SqlType(StandardTypes.DOUBLE) double f8, @SqlType(StandardTypes.DOUBLE) double f9)
{
return featuresHelper(f1, f2, f3, f4, f5, f6, f7, f8, f9);
}
@ScalarFunction
@SqlType(MAP_BIGINT_DOUBLE)
public static Block features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3, @SqlType(StandardTypes.DOUBLE) double f4, @SqlType(StandardTypes.DOUBLE) double f5, @SqlType(StandardTypes.DOUBLE) double f6, @SqlType(StandardTypes.DOUBLE) double f7, @SqlType(StandardTypes.DOUBLE) double f8, @SqlType(StandardTypes.DOUBLE) double f9, @SqlType(StandardTypes.DOUBLE) double f10)
{
return featuresHelper(f1, f2, f3, f4, f5, f6, f7, f8, f9, f10);
}
private static Block featuresHelper(double... features)
{
BlockBuilder blockBuilder = new InterleavedBlockBuilder(ImmutableList.of(BigintType.BIGINT, DoubleType.DOUBLE), new BlockBuilderStatus(), features.length);
for (int i = 0; i < features.length; i++) {
BigintType.BIGINT.writeLong(blockBuilder, i);
DoubleType.DOUBLE.writeDouble(blockBuilder, features[i]);
}
return blockBuilder.build();
}
}