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diff --git a/bigtop-data-generators/bigtop-weatherman/src/main/java/org/apache/bigtop/datagenerators/weatherman/internal/TemperatureSampler.java b/bigtop-data-generators/bigtop-weatherman/src/main/java/org/apache/bigtop/datagenerators/weatherman/internal/TemperatureSampler.java
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+++ b/bigtop-data-generators/bigtop-weatherman/src/main/java/org/apache/bigtop/datagenerators/weatherman/internal/TemperatureSampler.java
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+/**
+ * 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.bigtop.datagenerators.weatherman.internal;
+
+import org.apache.bigtop.datagenerators.samplers.SeedFactory;
+import org.apache.bigtop.datagenerators.samplers.samplers.ConditionalSampler;
+import org.apache.bigtop.datagenerators.samplers.samplers.GaussianSampler;
+import org.apache.bigtop.datagenerators.samplers.samplers.Sampler;
+import org.joda.time.LocalDate;
+
+public class TemperatureSampler implements
+        ConditionalSampler<WeatherRecordBuilder, WeatherRecordBuilder> {
+  final private Sampler<Double> R;
+  final private double average;
+  final private double coeffReal;
+  final private double coeffImag;
+
+  private LocalDate date;
+  private double noise;
+
+  public TemperatureSampler(LocalDate startDate, double tempAverage,
+          double tempRealCoeff, double tempImagCoeff, double tempSigma,
+          SeedFactory seedFactory) {
+    R = new GaussianSampler(0.0, tempSigma, seedFactory);
+
+    this.average = tempAverage;
+    this.coeffReal = tempRealCoeff;
+    this.coeffImag = tempImagCoeff;
+
+    date = startDate;
+    noise = 0.0;
+  }
+
+  public WeatherRecordBuilder sample(WeatherRecordBuilder weatherRecord)
+          throws Exception {
+    double temp = 0.0;
+    while (date.isEqual(weatherRecord.getDate())
+            || date.isBefore(weatherRecord.getDate())) {
+      double dayOfYear = date.getDayOfYear();
+      temp = average
+              + coeffReal * Math.cos(-2.0 * Math.PI * dayOfYear
+                      / WeatherConstants.TEMPERATURE_PERIOD)
+              + coeffImag * Math.sin(-2.0 * Math.PI * dayOfYear
+                      / WeatherConstants.TEMPERATURE_PERIOD)
+              + noise;
+
+      noise += -1.0 * noise * WeatherConstants.TEMPERATURE_GAMMA
+              * WeatherConstants.WEATHER_TIMESTEP
+              + Math.sqrt(WeatherConstants.WEATHER_TIMESTEP) * R.sample();
+
+      date = date.plusDays(WeatherConstants.WEATHER_TIMESTEP);
+    }
+
+    weatherRecord.setTemperature(temp);
+
+    return weatherRecord;
+  }
+}