有人可以帮我找到以下代码中的错误。我收到一个Java异常，但我不知道它为什么会发生。感谢您的关注！异常的描述如下：
> Exception in thread "main" java.lang.ExceptionInInitializerError
> Caused by: java.lang.ArrayIndexOutOfBoundsException
> at java.lang.System.arraycopy(Native Method)
> at org.ejml.data.DenseMatrix64F.set(Unknown Source)
> at org.ejml.data.DenseMatrix64F.<init>(Unknown Source)
> at org.ejml.simple.SimpleMatrix.<init>(Unknown Source)
> at test1.<clinit>(test1.java:14)
代码：
import org.ejml.simple.SimpleMatrix;
import java.lang.Math;
import java.util.Scanner;
public class test1 {
class testcase3 {
public testcase3() {
Mkt = 100000;
E1name = new SimpleMatrix(2, 5, true, -10, -5, 0, 5, 10, 1, 2, 3,
4, 5);
E1name2 = new SimpleMatrix(2, 5, true, 1, 2, 3, 4, 5, -10, -5, 0,
5, 10);
E2name = new SimpleMatrix(2, 2, true, 1, 3, 1, 2);
E2name2 = new SimpleMatrix(2, 2, true, 1, 2, 1, 3);
EM1 = new SimpleMatrix(2, 5, true, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
EM2 = new SimpleMatrix(2, 2, true, 0, 0, 0, 0);
T = new SimpleMatrix(2, 2, true, 0, 0, 0, 0);
Pa = new SimpleMatrix(1, 2, true, 0, 0);
Position = 0;
}
public double Mkt;
public SimpleMatrix E1name;
public SimpleMatrix E2name;
public SimpleMatrix E1name2;
public SimpleMatrix E2name2;
public SimpleMatrix EM1;
public SimpleMatrix EM2;
public SimpleMatrix T;
public SimpleMatrix Pa;
public int Position;
public int newBidAsk(double bidPrice, double askPrice) {
// log("I received a new Top-of-Book update, bid=" + bidPrice +
// ", offer=" + askPrice);
// data transformation
double newMkt = (bidPrice + askPrice) / 2;
double Grow = newMkt - Mkt;
double Spread = (askPrice - bidPrice) / 2;
SimpleMatrix seq = new SimpleMatrix(1, 2, true, Grow, Spread);
SimpleMatrix z = new SimpleMatrix(1, 2, true, 0, 0);
z.set(0, 0, Nametrans(seq.getIndex(0, 0), E1name));
z.set(0, 1, Nametrans(seq.getIndex(0, 1), E2name));
int act = 0;
// parameter updating
SimpleMatrix Px = Hmmupdate(Pa, z, EM1, EM2);
SimpleMatrix newPa = Hmmpredict(Px, T);
SimpleMatrix E1n = Hmmempredict(newPa, EM1, EM2, 5);
SimpleMatrix E2n = Hmmempredict(newPa, EM1, EM2, 2);
SimpleMatrix E = Eab(newMkt, E1n, E2n, E1name2, E2name2);
int E1 = E.getIndex(0, 0);
int E2 = E.getIndex(0, 1);
// action
if (Position == 0) {
int L = (int) Math.max(0,
Math.max(E1 - askPrice, bidPrice - E2));
switch (L) {
case 1:
act = 0;
break;
case 2:
act = 1;
break;
case 3:
act = -1;
break;
}
} else if (Position == -1) {
int L = (int) Math.max(-askPrice, -E1);
switch (L) {
case 1:
act = 1;
break;
case 2:
act = 0;
break;
}
} else if (Position == 1) {
int L = (int) Math.max(bidPrice, E2);
switch (L) {
case 1:
act = -1;
break;
case 2:
act = 0;
break;
}
}
Position = act + Position;
// log("The act is " + Position);
return Position;
}
public SimpleMatrix Eab(double Mkt, SimpleMatrix E1, SimpleMatrix E2,
SimpleMatrix E1name2, SimpleMatrix E2name2) {
SimpleMatrix Easkbid = new SimpleMatrix(1, 2, true, Mkt, Mkt);
for (int i = 0; i < 5; i++) {
for (int j = 0; j < 2; j++) {
Easkbid.set(0, 0,
Easkbid.getIndex(0, 0) + (Nametrans(i, E1name2))
* E1.getIndex(0, i) * E2.getIndex(0, j));
Easkbid.set(0, 1,
Easkbid.getIndex(0, 1) + (Nametrans(i, E2name2))
* E1.getIndex(0, i) * E2.getIndex(0, j));
}
}
return Easkbid;
}
public SimpleMatrix Hmmempredict(SimpleMatrix Pxkla, SimpleMatrix EM1,
SimpleMatrix EM2, int length) {
SimpleMatrix E = new SimpleMatrix(1, length, true);
for (int i = 0; i < 2; i++) {
for (int j = 0; j < length; j++) {
E.set(1,
j,
E.getIndex(1, j) + EM2.getIndex(i, j)
* Pxkla.getIndex(1, i));
}
}
E = normalize(E);
return E;
}
public SimpleMatrix Hmmpredict(SimpleMatrix Pxk, SimpleMatrix T) {
SimpleMatrix Pxkla = new SimpleMatrix(1, 2, true, 0, 0);
for (int i = 0; i < 2; i++) {
for (int j = 0; j < 2; j++) {
Pxkla.set(0, i, Pxkla.getIndex(0, i) + Pxkla.getIndex(0, j)
* T.getIndex(j, i));
}
}
Pxkla = normalize(Pxkla);
return Pxkla;
}
public SimpleMatrix Hmmupdate(SimpleMatrix Pxka, SimpleMatrix zk,
SimpleMatrix EM1, SimpleMatrix EM2) {
SimpleMatrix Pxk = new SimpleMatrix(1, 2, true, 0, 0);
for (int i = 0; i < 2; i++) {
Pxk.set(0,
i,
(Pxka.getIndex(0, i)
* EM1.getIndex(i, zk.getIndex(0, 0)) * EM2
.getIndex(i, zk.getIndex(0, 1))));
}
Pxk = normalize(Pxk);
return Pxk;
}
public SimpleMatrix normalize(SimpleMatrix B) {
double temp = 0;
for (int i = 0; i < B.numCols(); i++) {
temp = B.getIndex(0, i);
}
SimpleMatrix A = B;
for (int j = 0; j < A.numCols(); j++) {
A.set(0, j, B.getIndex(0, j) / temp);
}
return A;
}
public double Nametrans(double a, SimpleMatrix Nama) {
int n = Nama.numCols();
double b = 0;
for (int i = 0; i < n; i++) {
if (a == Nama.getIndex(0, i)) {
b = Nama.getIndex(1, i);
}
}
return b;
}
}
public static void main(String[] args) {
Scanner s = new Scanner(System.in);
double bid = s.nextDouble();
double ask = s.nextDouble();
testcase3 tc3;
int act = tc3.newBidAsk(bid, ask);
System.out.printf("%d", act);
}
}
答案 0 :(得分：0)
堆栈跟踪非常棒，它们会告诉您发生错误时的行 - 或者之后的行。关于你的代码我唯一能看到的就是负数;尝试制作没有它们的矩阵，看看是否能清除错误。如果是这样，你可以尝试在那里传递真正的双精度而不是必须由运行时转换的整数。
而且，如果确实如此，那么图书馆作家应该在他们的javadoc中提到它，或者你可能在他们的代码中发现了一个（恐怖！）主要错误。