tasks a-s

Task/Random-numbers/Modula-3/random-numbers.mod3

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+MODULE Rand EXPORTS Main;
+
+IMPORT Random;
+FROM Math IMPORT log, cos, sqrt, Pi;
+
+VAR rands: ARRAY [1..1000] OF LONGREAL;
+
+(* Normal distribution. *)
+PROCEDURE RandNorm(): LONGREAL =
+  BEGIN
+    WITH rand = NEW(Random.Default).init() DO
+      RETURN
+        sqrt(-2.0D0 * log(rand.longreal())) * cos(2.0D0 * Pi * rand.longreal());
+    END;
+  END RandNorm;
+
+BEGIN
+  FOR i := FIRST(rands) TO LAST(rands) DO
+    rands[i] := 1.0D0 + 0.5D0 * RandNorm();
+  END;
+END Rand.