com.github.brandtg.stl.PlotTest.java Source code

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Here is the source code for com.github.brandtg.stl.PlotTest.java

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/**
 * 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.github.brandtg.stl;

import java.io.BufferedReader;
import java.io.File;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;

import org.jfree.data.time.Hour;
import org.testng.Assert;
import org.testng.annotations.Test;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;

public class PlotTest {
    @Test
    public void testMinimalCase() throws Exception {
        List<Number> times = new ArrayList<Number>();
        List<Number> measures = new ArrayList<Number>();

        // Read from STDIN
        String line;
        BufferedReader reader = new BufferedReader(
                new InputStreamReader(ClassLoader.getSystemResourceAsStream("minimal.csv")));
        while ((line = reader.readLine()) != null) {
            String[] tokens = line.split(",");
            times.add(Long.valueOf(tokens[0]));
            measures.add(Double.valueOf(tokens[1]));
        }

        StlDecomposition stl = new StlDecomposition(288);
        stl.getConfig().setTrendComponentBandwidth(0.751);
        stl.getConfig().setSeasonalComponentBandwidth(0.85);
        // TODO: With default 10 we get decent results, but with 1 the head end seems a little off
        //    stl.getConfig().setNumberOfInnerLoopPasses(1);
        stl.getConfig().setPeriodic(false);
        StlResult res = stl.decompose(times, measures);

        // TODO: Validate more somehow (from https://github.com/brandtg/stl-java/issues/9)
        //    for (int i = 0; i < times.size(); i++) {
        //      System.out.println(String.format("%d,%02f,%02f,%02f,%02f",
        //          (long) res.getTimes()[i],
        //          res.getSeries()[i],
        //          res.getTrend()[i],
        //          res.getSeasonal()[i],
        //          res.getRemainder()[i]));
        //    }
    }

    @Test
    public void testPlot() throws Exception {
        final ObjectMapper objectMapper = new ObjectMapper();
        final JsonNode tree = objectMapper
                .readTree(new File(this.getClass().getResource("/sample-timeseries.json").getFile()));
        final int n = tree.get("times").size();
        final double[] ts = new double[n];
        final double[] ys = new double[n];

        for (int i = 0; i < n; i++) {
            ts[i] = tree.get("times").get(i).asDouble();
            ys[i] = tree.get("series").get(i).asDouble();
        }

        final StlDecomposition stl = new StlDecomposition(12);
        final StlResult res = stl.decompose(ts, ys);

        final File output = new File("seasonal.png");
        final File hourly = new File("stl-hourly.png");

        output.deleteOnExit();
        hourly.deleteOnExit();

        StlPlotter.plot(res, "New Title", Hour.class, hourly);
        StlPlotter.plot(res, output);
        StlPlotter.plot(res);

        Assert.assertTrue(output.exists());
        Assert.assertTrue(hourly.exists());

        final File exists = new File("stl-decomposition.png");
        exists.deleteOnExit();

        StlPlotter.plot(res, "Test Title");

        Assert.assertTrue(exists.exists());
    }
}