math/Rでの関数モデルの当てはめをrJava経由でやってみる

前回のRSampleと入れ替えて，データファイル(dist.dat)を用意してみる．

src/rJava/RSample.java

	package rJava;
	import org.rosuda.JRI.REXP;
	import org.rosuda.JRI.Rengine;
	public class RSample {
	public static void main(String[] args) {
	System.out.println("R_HOME:" + System.getenv("R_HOME"));
	System.out.println("java.library.path:"
	+ System.getProperty("java.library.path"));
	Rengine engine = new Rengine(new String[] {
	"--no-save"
	}, false, null);
	try {
	String filename = "dist.dat";
	engine.eval("data<-read.csv(\"" + filename + "\")");
	engine.eval("x<-data[,1]");
	engine.eval("y<-data[,2]");
	String[] exprs = {
	"a*x+b", "a*x^b", "a*b^x"
	};
	for (String expr : exprs) {
	double[] r = func(engine, expr);
	String out = expr;
	out += (": a=" + r[0]);
	out += (", b=" + r[1]);
	out += (" (AIC " + r[2] + ")");
	System.out.println(out);
	}
	} finally {
	engine.end();
	}
	}
	private static double[] func(Rengine engine, String f) {
	engine.eval("result<-nls(y~(" + f + "), start=c(a=1, b=1))");
	REXP result0 = engine.eval("summary(result)");
	REXP result1 = engine.eval("AIC(result)");
	double[] c = ((result0.asVector()).at("parameters")).asDoubleArray();
	double[] ret = {
	c[0], c[1], result1.asDouble()
	};
	return ret;
	}
	}

view raw RSample.java hosted with ❤ by GitHub

dist.dat

0,22
1,25
2,28
3,19
4,20
5,18
6,18
7,12
8,15
9,11
10,22
11,16
12,19
13,22
14,18
15,10
16,16
17,11
18,11
19,11
20,10
21,15
22,12
23,10
24,10
25,11
26,12
27,10
28,7
29,8
30,10
31,11
32,9
33,6
34,9
35,10
36,11
37,6
38,5
39,6
40,8
41,10
42,15
43,7
44,5
45,3
46,4
47,2
48,5
49,9
50,3
51,7
52,6
53,5
54,5
55,1
56,7
57,5
58,5
59,4
60,3
61,2
62,2
63,7
64,4
65,4
66,9
67,5
68,7
69,6
70,6
71,2
72,2
73,2
74,3
75,2
76,1
77,2
78,4
79,1
80,3
81,1
82,3
83,3
84,4
85,2
86,4
87,6
88,0
89,7
90,3
91,3
92,3
93,2
94,8
95,0
96,0
97,2
98,3
99,3
100,4
101,5
102,1
103,3
104,3
105,1
106,3
107,3
108,0
109,3
110,4
111,1
112,2
113,0
114,3
115,2
116,0
117,2
118,2
119,0
120,1
121,1
122,2
123,1
124,2
125,2
126,3
127,3
128,0
129,1
130,3
131,1
132,4
133,2
134,0
135,1
136,1
137,1
138,2
139,1
140,1
141,0
142,2
143,0
144,0
145,0
146,2
147,0
148,0
149,0
150,2
151,0
152,0
153,0
154,0
155,4
156,1
157,0
158,0
159,1
160,1
161,1
162,1
163,0
164,0
165,0
166,1
167,1
168,1
169,1
170,1
171,0
172,0
173,0
174,0
175,1
176,0
177,0
178,0
179,0
180,0
181,2
182,1
183,0
184,1
185,2
186,0
187,0
188,0
189,0
190,0
191,0
192,1
193,2
194,0
195,0
196,1
197,0
198,0
199,0
200,1
201,0
202,0
203,1
204,1
205,0
206,0
207,0
208,1
209,0
210,0
211,0
212,1
213,0
214,0
215,1
216,0
217,0
218,0
219,0
220,0
221,1
222,0
223,0
224,0
225,0
226,0
227,0
228,0
229,0
230,0
231,0
232,0
233,0
234,0
235,0
236,0
237,0
238,0
239,0
240,0
241,0
242,0
243,0
244,0
245,0
246,0
247,1
248,1
249,1
250,0
251,0
252,0
253,0
254,0
255,0
256,0
257,0
258,0
259,0
260,0
261,0
262,0
263,0
264,0
265,0
266,0
267,0
268,0
269,0
270,0
271,0
272,0
273,0
274,0
275,0
276,0
277,0
278,0
279,0
280,0
281,0
282,0
283,0
284,0
285,0
286,0
287,0
288,0
289,0
290,0
291,0
292,0
293,0
294,0
295,0
296,0
297,0
298,0
299,0
300,0
301,0
302,0
303,0
304,0
305,0
306,0
307,0
308,0
309,0
310,0
311,0
312,0
313,0
314,0
315,0
316,0
317,0
318,0
319,0
320,0
321,1
322,0
323,0
324,0
325,0
326,1

結果

R_HOME:/usr/local/Cellar/r/3.1.2/R.framework/Versions/3.1/Resources
java.library.path:.:/usr/local/Cellar/r/3.1.2/R.framework/Versions/3.1/Resources/library/rJava/jri
a*x+b: a=-0.03550333158708252, b=8.498046248230285  (AIC 1712.5095155708004)
a*x^b: a=39.75900134122691, b=-0.5633965054825036  (AIC 1550.0470141120295)
a*b^x: a=21.2572188567732, b=0.9751177432706232  (AIC 1240.9971794263668)

参考

• R言語で統計解析入門： 非線形回帰分析　A nonlinear regression analysis　梶山　喜一郎