1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
|
/**
* 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.GammaSampler;
import org.apache.bigtop.datagenerators.samplers.samplers.Sampler;
public class WindSpeedSampler implements
ConditionalSampler<WeatherRecordBuilder, WeatherRecordBuilder> {
private final double coeffReal;
private final double coeffImag;
private final Sampler<Double> gamma;
public WindSpeedSampler(double windSpeedRealCoeff, double windSpeedImagCoeff,
double windSpeedK, double windSpeedTheta, SeedFactory seedFactory) {
coeffReal = windSpeedRealCoeff;
coeffImag = windSpeedImagCoeff;
gamma = new GammaSampler(windSpeedK, windSpeedTheta, seedFactory);
}
/**
*
* @param temp
* - given in Fahrenheit
* @param windSpeed
* - given in MPH
* @return
*/
private Double windChill(double temp, double windSpeed) {
double v_16 = Math.pow(windSpeed, 0.16);
double windChill = 35.74 + 0.6215 * temp - 35.74 * v_16
+ 0.4275 * temp * v_16;
return windChill;
}
public WeatherRecordBuilder sample(WeatherRecordBuilder weatherRecord)
throws Exception {
double dayOfYear = weatherRecord.getDate().getDayOfYear();
// meters/second
double windSpeed = Math.max(0.0,
coeffReal
* Math.cos(-2.0 * Math.PI * dayOfYear
/ WeatherConstants.TEMPERATURE_PERIOD)
+ coeffImag * Math.sin(-2.0 * Math.PI * dayOfYear
/ WeatherConstants.TEMPERATURE_PERIOD) + gamma.sample());
double windChill = windChill(weatherRecord.getTemperature(),
windSpeed * WeatherConstants.M_PER_S_TO_MPH);
weatherRecord.setWindSpeed(windSpeed);
weatherRecord.setWindChill(windChill);
return weatherRecord;
}
}
|
