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之間我的課，我們給出的任務如下：估算區域形狀
在這個作業中，你會嘗試一個程序計算一組形狀的重疊區域，實現蒙特卡洛積分，正如課堂討論的那樣。 製作AreaEstimator.java，該程序使用隨機估計來估計任意數量的圓和三角形的重疊區域。該程序的參數將是這個試驗中隨機生成的點的數量，接下來是定義這些形狀的點的座標。例如，
的java AreaEstimator百萬圈2.0 2.0 1.0 1.0三角形1.0 2.5 3.0 2.0 -3.0 2.5圈1.0 3.0
將產生百萬隨機點來估計三角形，其頂點是（1.0，1.0的重疊），（2.5,3.0），（2.0，-3.0），其中兩個圓的中心位於（2.0,2.0）和（2.5,1.0），其半徑分別爲1.0和3.0。
這裏是我的Circle類代碼：
public class Circle {
private double xcenter;
private double ycenter;
private double radius;
private double xcmax;
private double xcmin;
private double ycmax;
private double ycmin;
public Circle (double xcenter, double ycenter, double radius){
if(radius <= 0){
throw new IllegalArgumentException();
}
this.xcenter = xcenter;
this.ycenter = ycenter;
this.radius = radius;
}
public void maxAndMinCircle(){ //find the minimun and maximum for the plane according to this circle
xcmax = (this.xcenter + this.radius);
ycmax = (this.ycenter + this.radius);
xcmin = (this.xcenter - this.radius);
ycmin = (this.ycenter - this.radius);
}
public double getXCMax(){
return xcmax;
}
public double getYCMax() {
return ycmax;
}
public double getXCMin() {
return xcmin;
}
public double getYCMin(){
return ycmin;
}
public boolean outsideCircle(double randX, double randY){ // find if the random point passed thru is in this circle
double distance = Math.sqrt((randX-this.xcenter)*(randX-this.xcenter) + (randY-this.ycenter) * (randY - this.ycenter));
return distance >= radius;
}}
三角類：
public class Triangle {
private double cornerx1;
private double cornery1;
private double cornerx2;
private double cornery2;
private double cornerx3;
private double cornery3;
private double xtmax;
private double xtmin;
private double ytmax;
private double ytmin;
private Double[] corners;
public Triangle (double cornerx1, double cornery1, double cornerx2, double cornery2, double cornerx3, double cornery3){
corners = new Double [6];
corners[0] = cornerx1;
corners[1] = cornery1;
corners[2] = cornerx2;
corners[3] = cornery2;
corners[4] = cornerx3;
corners[5] = cornery3;
}
public void maxAndMinTriangle(){ // find the minimum and maximum of the plane according to this triangle
xtmax = corners[0];
for(int i=1;i < corners.length;i += 2){
if(corners[i] > xtmax){
xtmax = corners[i];
}
}
xtmin = corners[0];
for(int i=1;i < corners.length;i += 2){
if(corners[i] < xtmin){
xtmin = corners[i];
}
}
ytmax = corners[1];
for(int i=1;i < corners.length;i += 2){
if(corners[i] > ytmax){
ytmax = corners[i];
}
}
ytmin = corners[1];
for(int i=1;i < corners.length;i += 2){
if(corners[i] < ytmin){
ytmin = corners[i];
}
}
}
public double getXTMax(){
return xtmax;
}
public double getYTMax() {
return ytmax;
}
public double getXTMin() {
return xtmin;
}
public double getYTMin(){
return ytmin;
}
//public static boolean isLeft (double x1, double y1, double x2, double y2, double x3, double y3){
//return (0 <= ((x2 - x1) * (y - y1))- ((y2 - y1) * (x - x1)));
//}
public boolean isLeft1 (double randX, double randY){ // find if this point is to the left of the first line
return (0 <= ((corners[2] - corners[0]) * (randY - corners[1]))- ((corners[3] - corners[1]) * (randX - corners[0])));
}
public boolean isLeft2 (double randX, double randY){ // find if this point is to the left of the second line
return (0 <= ((corners[4] - corners[0]) * (randY - corners[1]))- ((corners[5] - corners[1]) * (randX - corners[0])));
}
public boolean isLeft3 (double randX, double randY){ // find if this point is to the left of the third line
return (0 <= ((corners[4] - corners[2]) * (randY - corners[3]))- ((corners[5] - corners[3]) * (randX - corners[2])));
}
public boolean outsideTriangle (double randX, double randY){ // find if this point is inside of the triangle
int counter = 0;
if (isLeft1(randX,randY)){
counter++;
}
if (isLeft2(randX,randY)){
counter++;
}
if (isLeft3(randX,randY)){
counter++;
}
return counter == 2; // must be to the left of exactly 2 of the lines
}}
然後是AreaEstimator類：
public class AreaEstimator{
public static double[] maxAndMinValues (Circle[] circles,Triangle[] triangles){
// find maximum and minimum values according to all of the triangles and circles
double xmax = -100;
double ymax = -100;
double xmin = 100;
double ymin = 100;
for (int l=0; l < circles.length; l++){
if (xmax < circles[l].getXCMax()){
xmax = circles[l].getXCMax();
}
if (ymax < circles[l].getYCMax()){
ymax = circles[l].getYCMax();
}
if (xmin > circles[l].getXCMin()){
xmin = circles[l].getXCMin();
}
if (ymin > circles[l].getYCMin()){
ymin = circles[l].getYCMin();
}
}
for (int m = 0; m < triangles.length; m++){
if(xmax < triangles[m].getXTMax()){
xmax = triangles[m].getXTMax();
}
if(ymax < triangles[m].getYTMax()){
ymax = triangles[m].getYTMax();
}
if(xmin > triangles[m].getXTMin()){
xmin = triangles[m].getXTMin();
}
if(ymin > triangles[m].getYTMin()){
ymin = triangles[m].getYTMin();
}
}
double[] result = new double [4];
result[0] = xmax;
result[1] = ymax;
result[2] = xmin;
result[3] = ymin;
return result;
}
public static void main (String[] args) {
double numThrows = Integer.parseInt(args[0]); // initialize amount of throws
if (numThrows <= 0){
throw new IllegalArgumentException();
}
int countCircles = 0; // find the amount of circles given
for (int i = 1; i<args.length; i++){
if(args[i].equals("circle")){
countCircles++;
}
}
Circle[] circles = new Circle [countCircles];
for (int i = 1; i<args.length; i++){
if (args[i].equals("circle")){
for (int k = 0; k< countCircles; k++){
double xcenter = Double.parseDouble(args[i+1]);
double ycenter = Double.parseDouble(args[i+2]);
double radius = Double.parseDouble(args[i+3]);
circles[k] = new Circle (xcenter, ycenter, radius); //values associated with this circle
circles[k].maxAndMinCircle();//max and min value of the circle itself
}
}
}
int countTriangles = 0; // find the amount of the triangles given
for (int i = 1; i < args.length; i++){
if(args[i].equals("triangle")){
countTriangles++;
}
}
Triangle[] triangles = new Triangle [countTriangles];
for (int i = 1; i<args.length; i++){
if (args[i].equals("triangle")){
for (int p = 0; p< countTriangles; p++){
double cornerx1 = Double.parseDouble(args[i+1]);
double cornery1 = Double.parseDouble(args[i+2]);
double cornerx2 = Double.parseDouble(args[i+3]);
double cornery2 = Double.parseDouble(args[i+4]);
double cornerx3 = Double.parseDouble(args[i+5]);
double cornery3 = Double.parseDouble(args[i+6]);
triangles[p] = new Triangle (cornerx1, cornery1, cornerx2, cornery2, cornerx3, cornery3);
//values associated with this triangle
triangles[p].maxAndMinTriangle(); //max and min value of the triangle itself
}
}
}
boolean dartsInOverlap = true;
double countInOverlap = 0; // initialize amount of darts in the overlapping shape
double[]result = maxAndMinValues(circles,triangles);
for(int i= 0;i < numThrows;i++){
double randX= (Math.random() * (result[0]-result[2]) + result[2]) ; // generate a random x value
double randY= (Math.random() * (result[1]-result[3])+ result[3]); // generate a random y value
for (int h = 0; h < circles.length && dartsInOverlap; h++){
if (circles[h].outsideCircle(randX, randY)){
dartsInOverlap = false; // if the point is outside of the circle, it returns false
}
}
for (int q = 0; q < triangles.length && dartsInOverlap; q++){
if (triangles[q].outsideTriangle(randX, randY)){
dartsInOverlap = false; // if the point is outside of the triangle, it returns false
}
}
if (dartsInOverlap){
countInOverlap++; // counts up the amount of points in the overlapping shape
}
dartsInOverlap = true;
}
System.out.println("This many darts were in the overlap between the shapes:" + countInOverlap);
// counts up the amount of points in the overlapping shape
System.out.println("The estimated overlapped areas is" + (result[0]-result[2])*(result[1]-result[3]) *(countInOverlap/numThrows));
//finds estimated area
}}
我的代碼工作對於少數測試用例，如果在命令行中只有一個進入的圓圈和三角形，或者只有一個唯一的圓圈。一個三角形本身或任何其他組合將給我的答案遠離所需的區域估計。我查看並審查了我的代碼，這一切似乎都合乎邏輯。那麼，在我的代碼中，問題仍然存在？任何幫助，將不勝感激。