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所以在我的編程課,我們正在學習使用繪圖類。基本上畫一條線和東西,我們在課上做了一條y=mx+b
線。對數螺旋
我想跳起來,開始做更瘋狂的數學!
雖然我在普林斯頓大學的網站上找到了,但我仍然遇到了麻煩。
public class Spiral {
public static void main(String[] args) {
int N = Integer.parseInt(args[0]); // # sides if decay = 1.0
double decay = Double.parseDouble(args[1]); // decay factor
double angle = 360.0/N;
double step = Math.sin(Math.toRadians(angle/2.0));
Turtle turtle = new Turtle(0.5, 0.0, angle/2.0);
for (int i = 0; i < 10*N; i++) {
step /= decay;
turtle.goForward(step);
turtle.turnLeft(angle);
}
}
}
import java.awt.Color;
public class Turtle {
private double x, y; // turtle is at (x, y)
private double angle; // facing this many degrees counterclockwise from the x-axis
// start at (x0, y0), facing a0 degrees counterclockwise from the x-axis
public Turtle(double x0, double y0, double a0) {
x = x0;
y = y0;
angle = a0;
}
// rotate orientation delta degrees counterclockwise
public void turnLeft(double delta) {
angle += delta;
}
// move forward the given amount, with the pen down
public void goForward(double step) {
double oldx = x;
double oldy = y;
x += step * Math.cos(Math.toRadians(angle));
y += step * Math.sin(Math.toRadians(angle));
StdDraw.line(oldx, oldy, x, y);
}
// pause t milliseconds
public void pause(int t) {
StdDraw.show(t);
}
public void setPenColor(Color color) {
StdDraw.setPenColor(color);
}
public void setPenRadius(double radius) {
StdDraw.setPenRadius(radius);
}
public void setCanvasSize(int width, int height) {
StdDraw.setCanvasSize(width, height);
}
public void setXscale(double min, double max) {
StdDraw.setXscale(min, max);
}
public void setYscale(double min, double max) {
StdDraw.setYscale(min, max);
}
// sample client for testing
public static void main(String[] args) {
double x0 = 0.5;
double y0 = 0.0;
double a0 = 60.0;
double step = Math.sqrt(3)/2;
Turtle turtle = new Turtle(x0, y0, a0);
turtle.goForward(step);
turtle.turnLeft(120.0);
turtle.goForward(step);
turtle.turnLeft(120.0);
turtle.goForward(step);
turtle.turnLeft(120.0);
}
}
龜使用這個類:StdDraw
這只是編碼方式太多了線我在這裏貼上。
我不斷收到一個錯誤,當我去執行螺旋:
java.lang.ArrayIndexOutOfBoundsException: 0
at Spiral.main(Spiral.java:4)
不知道爲什麼。任何人都可以幫助我,讓我可以玩這個嗎?
我做過嘗試,但它給了我同樣的錯誤不管是什麼。你使用了什麼值? 我也在BlueJ上運行這個。 – 2011-02-15 06:11:29