Data commit

Task/Modified-random-distribution/Java/modified-random-distribution.java

@@ -0,0 +1,54 @@
+import java.util.List;
+import java.util.concurrent.ThreadLocalRandom;
+import java.util.stream.Stream;
+
+interface ModifierInterface {	
+	double modifier(double aDouble);	
+}
+
+public final class ModifiedRandomDistribution222 {
+
+	public static void main(String[] aArgs) {
+		final int sampleSize = 100_000;
+		final int binCount = 20;
+		final double binSize = 1.0 / binCount;
+		
+		List<Integer> bins = Stream.generate( () -> 0 ).limit(binCount).toList();
+		
+	    for ( int i = 0; i < sampleSize; i++ ) {
+	    	double random = modifiedRandom(modifier);
+	        int binNumber = (int) Math.floor(random / binSize);
+	        bins.set(binNumber, bins.get(binNumber) + 1);
+	    }
+		
+		System.out.println("Modified random distribution with " + sampleSize + " samples in range [0, 1):");
+		System.out.println();
+		System.out.println("    Range           		  Number of samples within range");
+		
+		final int scaleFactor = 125;
+		for ( int i = 0; i < binCount; i++ ) {
+			String histogram = String.valueOf("#").repeat(bins.get(i) / scaleFactor);
+			System.out.println(String.format("%4.2f ..< %4.2f %s %s",
+				(float) i / binCount, (float) ( i + 1.0 ) / binCount, histogram, bins.get(i)));			
+		}		
+	}
+	
+	private static double modifiedRandom(ModifierInterface aModifier) {
+		double result = -1.0;
+		
+		while ( result < 0.0 ) {
+			double randomOne = RANDOM.nextDouble();
+			double randomTwo = RANDOM.nextDouble();
+			if ( randomTwo < aModifier.modifier(randomOne) ) {
+				result = randomOne;
+			}
+		}
+		
+		return result;		
+	}		
+	
+	private static ModifierInterface modifier = aX -> ( aX < 0.5 ) ? 2 * ( 0.5 - aX ) : 2 * ( aX - 0.5 );	
+	
+	private static final ThreadLocalRandom RANDOM = ThreadLocalRandom.current();
+
+}