Pseudo-random numbers/Combined recursive generator MRG32k3a: Difference between revisions

Content added Content deleted
(Corrected output.)
Line 544: Line 544:
4 : 19931
4 : 19931
</pre>
</pre>

=={{header|Java}}==
{{trans|C++}}
<lang java>public class App {
private static long mod(long x, long y) {
long m = x % y;
if (m < 0) {
if (y < 0) {
return m - y;
} else {
return m + y;
}
}
return m;
}

public static class RNG {
// first generator
private final long[] a1 = {0, 1403580, -810728};
private static final long m1 = (1L << 32) - 209;
private long[] x1;
// second generator
private final long[] a2 = {527612, 0, -1370589};
private static final long m2 = (1L << 32) - 22853;
private long[] x2;
// other
private static final long d = m1 + 1;

public void seed(long state) {
x1 = new long[]{state, 0, 0};
x2 = new long[]{state, 0, 0};
}

public long nextInt() {
long x1i = mod(a1[0] * x1[0] + a1[1] * x1[1] + a1[2] * x1[2], m1);
long x2i = mod(a2[0] * x2[0] + a2[1] * x2[1] + a2[2] * x2[2], m2);
long z = mod(x1i - x2i, m1);

// keep the last three values of the first generator
x1 = new long[]{x1i, x1[0], x1[1]};
// keep the last three values of the second generator
x2 = new long[]{x2i, x2[0], x2[1]};

return z + 1;
}

public double nextFloat() {
return 1.0 * nextInt() / d;
}
}

public static void main(String[] args) {
RNG rng = new RNG();

rng.seed(1234567);
System.out.println(rng.nextInt());
System.out.println(rng.nextInt());
System.out.println(rng.nextInt());
System.out.println(rng.nextInt());
System.out.println(rng.nextInt());
System.out.println();

int[] counts = {0, 0, 0, 0, 0};
rng.seed(987654321);
for (int i = 0; i < 100_000; i++) {
int value = (int) Math.floor(rng.nextFloat() * 5.0);
counts[value]++;
}
for (int i = 0; i < counts.length; i++) {
System.out.printf("%d: %d%n", i, counts[i]);
}
}
}</lang>
{{out}}
<pre>1459213977
2827710106
4245671317
3877608661
2595287583

0: 20002
1: 20060
2: 19948
3: 20059
4: 19931</pre>


=={{header|Julia}}==
=={{header|Julia}}==
Retrieved from "https://rosettacode.org/wiki/Pseudo-random_numbers/Combined_recursive_generator_MRG32k3a"