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package algs32.kdtree;
import algs12.Point2D;
import algs13.Queue;
import stdlib.*;
/*
* Example output:
*
* 500: kd=0.041000 brute=0.035000
* 1000: kd=0.021000 brute=0.022000
* 2000: kd=0.007000 brute=0.050000
* 4000: kd=0.008000 brute=0.073000
* 8000: kd=0.018000 brute=0.156000
* 16000: kd=0.018000 brute=0.304000
* 32000: kd=0.052000 brute=0.730000
* 64000: kd=0.095000 brute=2.359000
* 128000: kd=0.163000 brute=4.735000
* 256000: kd=0.260000 brute=11.390000
* 512000: kd=1.499000 brute=27.822000
*/
public class RangeSearchPerformanceTest {
static int NUM_SIZES = 12;
public static void main(String[] args) {
Queue<RectHV> queue = new Queue<> ();
while (queue.size () < 1000) {
double x1 = Math.random ();
double x2 = Math.random ();
double y1 = Math.random ();
double y2 = Math.random ();
double xmin = Math.min (x1, x2);
double xmax = Math.max (x1, x2);
double ymin = Math.min (y1, y2);
double ymax = Math.max (y1, y2);
RectHV rect = new RectHV (xmin, ymin, xmax, ymax);
if (rect.width () * rect.height () > 0.01)
continue; // rectangle is too large
queue.enqueue(rect);
}
int N = 250;
for (int count=1; count<NUM_SIZES; count++) {
N += N;
PointSET brute = new PointSET();
KdTree kdtree = new KdTree();
for (int i=0; i<N; i++) {
Point2D p = new Point2D(Math.random(), Math.random());
RangeSearchCorrectnessTest.insert (kdtree, p);
brute.insert(p);
}
Stopwatch sw1 = new Stopwatch ();
for (RectHV r : queue)
RangeSearchCorrectnessTest.range (kdtree, r);
double d1 = sw1.elapsedTime ();
Stopwatch sw2 = new Stopwatch ();
for (RectHV r : queue)
brute.range (r);
double d2 = sw2.elapsedTime ();
StdOut.format ("%d: kd=%f brute=%f\n", N, d1, d2);
}
}
}
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