Data update

Task/Modified-random-distribution/XPL0/modified-random-distribution.xpl0

@@ -0,0 +1,39 @@
+include xpllib;         \for Print
+
+func real Modifier(X);
+real X;
+return if X < 0.5 then 2.*(0.5-X) else 2.*(X-0.5);
+
+func real RGen;
+return float(Ran(1_000_000)) / 1e6;
+
+func real RNG;
+real R1, R2;
+[loop   [R1:= RGen;
+         R2:= RGen;
+         if R2 < Modifier(R1) then
+             return R1;
+        ];
+];
+
+def  N = 100_000;
+def  NUM_BINS = 20;
+def  HIST_CHAR = ^#;
+def  HIST_CHAR_SIZE = 125;
+def  BinSize = 1. / float(NUM_BINS);
+int  Bins(NUM_BINS), BN, I, J, Hist;
+real RN;
+[for I:= 0 to N-1 do
+    [RN:= RNG;
+    BN:= fix(Floor(RN/BinSize));
+    Bins(BN):= Bins(BN)+1;
+    ];
+Print("Modified random distribution with %,d samples in range [0, 1):\n", N);
+Print("    Range           Number of samples within that range\n");
+for I:= 0 to NUM_BINS-1 do
+    [Hist:= Bins(I) / HIST_CHAR_SIZE;
+    Print("%1.2f ..< %1.2f  ", BinSize*float(I), BinSize*float(I+1));
+    for J:= 1 to Hist do Print("%c", HIST_CHAR);
+    Print(" %,d\n", Bins(I));
+    ];
+]