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package algs32.kdtree;
import algs12.Point2D;
import algs13.Queue;
import stdlib.*;
/*
* If the output looks like this, then you have a bug!
*
* 500: kd=0.146000 brute=0.021000
* 1000: kd=0.034000 brute=0.015000
* 2000: kd=0.052000 brute=0.032000
* 4000: kd=0.082000 brute=0.053000
* 8000: kd=0.175000 brute=0.108000
* 16000: kd=0.308000 brute=0.224000
* 32000: kd=0.649000 brute=0.508000
* 64000: kd=1.329000 brute=2.123000
* 128000: kd=3.375000 brute=4.144000
* 256000: kd=7.147000 brute=10.214000
* 512000: kd=18.383000 brute=26.161000
*
* Output should look like this:
*
* 500: kd=0.054000 brute=0.026000
* 1000: kd=0.036000 brute=0.018000
* 2000: kd=0.008000 brute=0.038000
* 4000: kd=0.011000 brute=0.063000
* 8000: kd=0.013000 brute=0.178000
* 16000: kd=0.019000 brute=0.274000
* 32000: kd=0.037000 brute=0.895000
* 64000: kd=0.050000 brute=2.099000
* 128000: kd=0.089000 brute=4.416000
* 256000: kd=0.082000 brute=10.716000
* 512000: kd=3.682000 brute=27.141000
*
* This is also okay:
*
* 500: kd=0.002000 brute=0.033000
* 1000: kd=0.001000 brute=0.014000
* 2000: kd=0.000000 brute=0.034000
* 4000: kd=0.000000 brute=0.098000
* 8000: kd=0.000000 brute=0.197000
* 16000: kd=0.001000 brute=0.407000
* 32000: kd=0.000000 brute=1.654000
* 64000: kd=0.000000 brute=3.241000
* 128000: kd=0.000000 brute=6.194000
* 256000: kd=0.000000 brute=13.980000
*/
public class NearestNeighborPerformanceTest {
static int NUM_SIZES = 11;
public static void main(String[] args) {
Queue<Point2D> queue = new Queue<> ();
for (int i=0; i<1000; i++)
queue.enqueue(new Point2D(Math.random(), Math.random()));
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());
NearestNeighborCorrectnessTest.insert (kdtree, p);
brute.insert(p);
}
Stopwatch sw1 = new Stopwatch ();
for (Point2D p : queue)
NearestNeighborCorrectnessTest.nearest (kdtree, p);
double d1 = sw1.elapsedTime ();
Stopwatch sw2 = new Stopwatch ();
for (Point2D p : queue)
brute.nearest (p);
double d2 = sw2.elapsedTime ();
StdOut.format ("%d: kd=%f brute=%f\n", N, d1, d2);
}
}
}
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