pgtwitter/RSample.java

## RSample.java
package rJava;

import java.io.File;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.util.Base64;

import org.rosuda.JRI.Rengine;

public class RSample {
	public static void main(String[] args) throws IOException {
		Rengine engine = new Rengine(new String[] {
			"--no-save"
		}, false, null);

		try {
			int n = 1000;
			double[] x = new double[n];
			for (int i = 0; i < n; i++) {
				x[i] = 0.0;
				for (int j = 0; j < 8; j++)
					x[i] += Math.random();
				x[i] = (x[i] - 4.0);
			}
			File file = File.createTempFile("plot", ".svg");
			file.deleteOnExit();

			engine.assign("x", x);
			engine.eval("svg('" + file.getAbsolutePath() + "')");
			engine.eval("hist(x, xlim=c(-4,4), ylim=c(0,0.6), prob=T, ann=F, panel.first = grid())");
			engine.eval("par(new=T)");
			engine.eval("plot(density(x), xlim=c(-4,4), ylim=c(0,0.6), xlab='' , ylab='' , main='' , col='red' )");
			engine.eval("dev.off()");

			byte[] bytes = Files.readAllBytes(file.toPath());
			String content = new String(bytes, StandardCharsets.UTF_8);
			content = content.substring(content.indexOf('\n'));
			String out = "<html><body>\n";
			out += content;
			out += "\n</body></html>";
			System.out.println(out);
		} finally {
			engine.end();
		}
	}
}
	package rJava;

	import java.io.File;
	import java.io.IOException;
	import java.nio.charset.StandardCharsets;
	import java.nio.file.Files;
	import java.util.Base64;

	import org.rosuda.JRI.Rengine;

	public class RSample {
	public static void main(String[] args) throws IOException {
	Rengine engine = new Rengine(new String[] {
	"--no-save"
	}, false, null);

	try {
	int n = 1000;
	double[] x = new double[n];
	for (int i = 0; i < n; i++) {
	x[i] = 0.0;
	for (int j = 0; j < 8; j++)
	x[i] += Math.random();
	x[i] = (x[i] - 4.0);
	}
	File file = File.createTempFile("plot", ".svg");
	file.deleteOnExit();

	engine.assign("x", x);
	engine.eval("svg('" + file.getAbsolutePath() + "')");
	engine.eval("hist(x, xlim=c(-4,4), ylim=c(0,0.6), prob=T, ann=F, panel.first = grid())");
	engine.eval("par(new=T)");
	engine.eval("plot(density(x), xlim=c(-4,4), ylim=c(0,0.6), xlab='' , ylab='' , main='' , col='red' )");
	engine.eval("dev.off()");

	byte[] bytes = Files.readAllBytes(file.toPath());
	String content = new String(bytes, StandardCharsets.UTF_8);
	content = content.substring(content.indexOf('\n'));
	String out = "<html><body>\n";
	out += content;
	out += "\n</body></html>";
	System.out.println(out);
	} finally {
	engine.end();
	}
	}
	}