Sync

Task/Random-numbers/C++/random-numbers-1.cpp

@@ -8,7 +8,7 @@ int main()
 {
   random_device seed;
   mt19937 engine(seed());
-  normal_distribution<> dist(1.0, 0.5);
+  normal_distribution<double> dist(1.0, 0.5);
   auto rnd = bind(dist, engine);
 
   vector<double> v(1000);

Task/Random-numbers/D/random-numbers-1.d

@@ -3,22 +3,23 @@ import std.stdio, std.random, std.math;
 struct NormalRandom {
     double mean, stdDev;
 
-    // needed because it also defines an opCall
+    // Necessary because it also defines an opCall.
     this(in double mean_, in double stdDev_) pure nothrow {
         this.mean = mean_;
         this.stdDev = stdDev_;
     }
 
     double opCall() const /*nothrow*/ {
-        immutable double r1 = uniform(0.0, 1.0);
-        immutable double r2 = uniform(0.0, 1.0);
-        return mean + stdDev * sqrt(-2 * log(r1)) * cos(2 * PI * r2);
+        immutable r1 = uniform(0.0, 1.0), // Not nothrow.
+                  r2 = uniform(0.0, 1.0);
+        return mean + stdDev * sqrt(-2 * r1.log) * cos(2 * PI * r2);
     }
 }
 
 void main() {
     double[1000] array;
-    auto nrnd = NormalRandom(1.0, 0.5);
+    auto nRnd = NormalRandom(1.0, 0.5);
     foreach (ref x; array)
-        x = nrnd();
+        //x = nRnd;
+        x = nRnd();
 }

Task/Random-numbers/Nimrod/random-numbers.nimrod

@@ -0,0 +1,14 @@
+import math, strutils
+
+const  precisn = 5
+var rs: TRunningStat
+
+proc normGauss: float {.inline.} = 1 + 0.76 * cos(2*PI*random(1.0)) * sqrt(-2*log10(random(1.0)))
+
+randomize()
+
+for j in 0..5:
+   for i in 0..1000:
+      rs.push(normGauss())
+   echo("mean: ", $formatFloat(rs.mean,ffDecimal,precisn),
+        " stdDev: ", $formatFloat(rs.standardDeviation(),ffDecimal,precisn))

Task/Random-numbers/Perl-6/random-numbers.pl6

@@ -2,4 +2,8 @@ sub randnorm ($mean, $stddev) {
     $mean + $stddev * sqrt(-2 * log rand) * cos(2 * pi * rand)
 }
 
-my @nums = map { randnorm 1, 0.5 }, ^1000;
+my @nums = randnorm(1, 0.5) xx 1000;
+
+# Checking
+say my $mean = @nums R/ [+] @nums;
+say my $stddev = sqrt $mean**2 R- @nums R/ [+] @nums X** 2;

Task/Random-numbers/SAS/random-numbers.sas

@@ -0,0 +1,12 @@
+/* Generate 1000 random numbers with mean 1 and standard deviation 0.5.
+  SAS version 9.2 was used to create this code.*/
+
+data norm1000;
+  call streaminit(123456);
+/* Set the starting point, so we can replicate results.
+   If you want different results each time, comment the above line. */
+  do i=1 to 1000;
+    r=rand('normal',1,0.5);
+    output;
+  end;
+run;

Task/Random-numbers/TorqueScript/random-numbers.torque

@@ -0,0 +1,2 @@
+for (%i = 0; %i < 1000; %i++)
+	%list[%i] = 1 + mSqrt(-2 * mLog(getRandom())) * mCos(2 * $pi * getRandom());