grainier commented on code in PR #132: URL: https://github.com/apache/incubator-streampipes/pull/132#discussion_r1014795317
########## streampipes-extensions/streampipes-processors-change-detection-jvm/src/main/java/org/apache/streampipes/processors/changedetection/jvm/welford/WelfordChangeDetection.java: ########## @@ -0,0 +1,150 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You 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 org.apache.streampipes.processors.changedetection.jvm.welford; + +import org.apache.streampipes.commons.exceptions.SpRuntimeException; +import org.apache.streampipes.model.DataProcessorType; +import org.apache.streampipes.model.graph.DataProcessorDescription; +import org.apache.streampipes.model.runtime.Event; +import org.apache.streampipes.model.schema.PropertyScope; +import org.apache.streampipes.processors.changedetection.jvm.cusum.CusumEventFields; +import org.apache.streampipes.sdk.builder.ProcessingElementBuilder; +import org.apache.streampipes.sdk.builder.StreamRequirementsBuilder; +import org.apache.streampipes.sdk.extractor.ProcessingElementParameterExtractor; +import org.apache.streampipes.sdk.helpers.*; +import org.apache.streampipes.sdk.utils.Assets; +import org.apache.streampipes.vocabulary.SO; +import org.apache.streampipes.wrapper.context.EventProcessorRuntimeContext; +import org.apache.streampipes.wrapper.routing.SpOutputCollector; +import org.apache.streampipes.wrapper.standalone.ProcessorParams; +import org.apache.streampipes.wrapper.standalone.StreamPipesDataProcessor; + +import java.util.Arrays; +import java.util.List; + +public class WelfordChangeDetection extends StreamPipesDataProcessor { + + private static final String NUMBER_MAPPING = "number-mapping"; + private static final String PARAM_K = "param-k"; + private static final String PARAM_H = "param-h"; + + private String selectedNumberMapping; + private Double k; + private Double h; + private Double cuSumLow; + private Double cuSumHigh; + private WelfordAggregate welfordAggregate; + + @Override + public DataProcessorDescription declareModel() { + return ProcessingElementBuilder.create("org.apache.streampipes.processors.changedetection.jvm.welford") + .category(DataProcessorType.VALUE_OBSERVER) + .withAssets(Assets.DOCUMENTATION) + .withAssets(Assets.ICON) + .withLocales(Locales.EN) + .requiredStream(StreamRequirementsBuilder + .create() + .requiredPropertyWithUnaryMapping(EpRequirements.numberReq(), + Labels.withId(NUMBER_MAPPING), + PropertyScope.NONE).build()) + .requiredFloatParameter(Labels.withId(PARAM_K), 0.0f, 0.0f, 100.0f, 0.01f) + .requiredFloatParameter(Labels.withId(PARAM_H), 0.0f, 0.0f, 100.0f, 0.01f) + .outputStrategy( + OutputStrategies.append( + Arrays.asList( + EpProperties.numberEp(Labels.empty(), WelfordEventFields.VAL_LOW.label, SO.Number), + EpProperties.numberEp(Labels.empty(), WelfordEventFields.VAL_HIGH.label, SO.Number), + EpProperties.booleanEp(Labels.empty(), WelfordEventFields.DECISION_LOW.label, SO.Boolean), + EpProperties.booleanEp(Labels.empty(), WelfordEventFields.DECISION_HIGH.label, SO.Boolean) + ) + )) + .build(); + } + + @Override + public void onInvocation(ProcessorParams parameters, SpOutputCollector spOutputCollector, EventProcessorRuntimeContext runtimeContext) throws SpRuntimeException { + + ProcessingElementParameterExtractor extractor = parameters.extractor(); + this.selectedNumberMapping = extractor.mappingPropertyValue(NUMBER_MAPPING); + this.k = extractor.singleValueParameter(PARAM_K, Double.class); + this.h = extractor.singleValueParameter(PARAM_H, Double.class); + this.cuSumLow = 0.0; + this.cuSumHigh = 0.0; + this.welfordAggregate = new WelfordAggregate(); + + } + + @Override + public void onEvent(Event event, SpOutputCollector collector) throws SpRuntimeException { + + Double number = event.getFieldBySelector(selectedNumberMapping).getAsPrimitive().getAsDouble(); + welfordAggregate.update(number); // update mean and standard deviation + Double normalized = getZScoreNormalizedValue(number); + updateStatistics(normalized); + Review Comment: ```suggestion ``` -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
