Java Small example: print an approximate circle, requiring the size of a given radius to change

For example: through the API document query math class method, print the following approximate circle, as long as given a different radius, the size of the circle changes.

    Import Java.lang.Math;  public class Mathdraw {/** * drawing function, input circle radius, Output circle */public static void paint (int    R) {//Assuming the center of the circle at coordinates (r,r) int x = 0;//x coordinates start int y = R * 2; The coordinates of y begin int c = 0; Middle space quantity int z = 2;  
      
           Decrements per line, and the step size is set to 2 to adjust the aspect ratio of the screen.  
               for (int i = R * 2; I >= 0; i = i-z) {//get x Value x = GetX (r, y) of the coordinates of the drawing * point;  
               First draw the Y-value on the left side of the * System.out.print (Getspace (x) + "*"); c = (r-x) *2;  
               With the center of the output space//and then draw the Y-value on the right side of the * SYSTEM.OUT.PRINTLN (Getspace (c) + "*");  
            Decreasing the Y value each time y-=z;  }/** * Get picture * position, Input circle radius and coordinate y value, output coordinate x value/public static int GetX (int   
           R, int y) {//Take the long side of the right-angled triangle int h = y-r; Find the triangle short side long double L = math.sqrt (R * r)-(H * h));  
        Taking the X value, Math.Round () returns the nearest integer return (int) math.round (r-l); /** * Draw space */public static string getspace (int i) {string  
            s = "";  
            for (int j = 0; J < i; J +) {s + = "";  
        return s;   
        The public static void main (string[] args) {//calls the drawing function, and the parameter is the radius of the circle paint (6);   }  
    }

To run the program:

Another one:

public class Circledraw {    /**      * @param args      * @author Bigboy &  nbsp;    *     public static void Main (string[] args) {        //  TODO auto-generated Method stub         //definition radius         int R
= 6;         //defines y as the ordinate of a circle, where y=y+2 is the step to set the ordinate, you can adjust the ellipse's "fat thin"         for (int y = 0; y <= 2 * r; y = y + 2) {            long x = MATH.R
Ound (R-MATH.SQRT (2 * R * y-y * y));             for (int i = 0; I <= 2 * r; i++) {   &NBSP;&NBSP;&N Bsp          //i==x refers to a vertical axis corresponding to a ordinate, i==2*r-x refers to the ordinate corresponding to the second horizontal axis                  if (i = = X | | | = = 2 * r-x) {                    system.out.print ("*");                &nbsp} else {       &
nbsp;            system.out.print ("");                &nbsp}         &
nbsp;   }             system.out.print ("\ n");


         }    &nbsp}

To run the program: