Data commit

Task/Bernoulli-numbers/C-sharp/bernoulli-numbers-1.cs

@@ -0,0 +1,53 @@
+using Mpir.NET;
+using System;
+
+namespace Bernoulli
+{
+    class Program
+    {
+        private static void bernoulli(mpq_t rop, uint n)
+        {
+            mpq_t[] a = new mpq_t[n + 1];
+
+            for (uint i = 0; i < n + 1; i++)
+            {
+                a[i] = new mpq_t();
+            }
+
+            for (uint m = 0; m <= n; ++m)
+            {
+                mpir.mpq_set_ui(a[m], 1, m + 1);
+
+                for (uint j = m; j > 0; --j)
+                {
+                    mpir.mpq_sub(a[j - 1], a[j], a[j - 1]);
+                    mpir.mpq_set_ui(rop, j, 1);
+                    mpir.mpq_mul(a[j - 1], a[j - 1], rop);
+                }
+
+                mpir.mpq_set(rop, a[0]);
+            }
+        }
+
+        static void Main(string[] args)
+        {
+            mpq_t rop = new mpq_t();
+            mpz_t n = new mpz_t();
+            mpz_t d = new mpz_t();
+
+            for (uint  i = 0; i <= 60; ++i)
+            {
+                bernoulli(rop, i);
+
+                if (mpir.mpq_cmp_ui(rop, 0, 1) != 0)
+                {
+                    mpir.mpq_get_num(n, rop);
+                    mpir.mpq_get_den(d, rop);
+                    Console.WriteLine(string.Format("B({0, 2}) = {1, 44} / {2}", i, n, d));
+                }
+            }
+
+            Console.ReadKey();
+        }
+    }
+}

Task/Bernoulli-numbers/C-sharp/bernoulli-numbers-2.cs

@@ -0,0 +1,51 @@
+using System;
+using System.Console;
+using System.Linq;
+using MathNet.Numerics;
+
+namespace Rosettacode.Rational.CS
+{
+    class Program
+    {
+        private static readonly Func<int, BigRational> ℚ = BigRational.FromInt;
+
+        private static BigRational CalculateBernoulli(int n)
+        {
+            var a = InitializeArray(n);
+
+            foreach(var m in Enumerable.Range(1,n))
+            {
+                a[m] = ℚ(1) / (ℚ(m) + ℚ(1));
+
+                for (var j = m; j >= 1; j--)
+                {
+                    a[j-1] = ℚ(j) * (a[j-1] - a[j]);
+                }
+            }
+
+            return a[0];
+        }
+
+        private static BigRational[] InitializeArray(int n)
+        {
+            var a = new BigRational[n + 1];
+
+            for (var x = 0; x < a.Length; x++)
+            {
+                a[x] = ℚ(x + 1);
+            }
+
+            return a;
+        }
+
+        static void Main()
+        {
+            Enumerable.Range(0, 61) // the second parameter is the number of range elements, and is not the final item of the range.
+                .Select(n => new {N = n, BernoulliNumber = CalculateBernoulli(n)})
+                .Where(b => !b.BernoulliNumber.Numerator.IsZero)
+                .Select(b => string.Format("B({0, 2}) = {1, 44} / {2}", b.N, b.BernoulliNumber.Numerator, b.BernoulliNumber.Denominator))
+                .ToList()
+                .ForEach(WriteLine);
+        }
+    }
+}

Task/Bernoulli-numbers/C-sharp/bernoulli-numbers-3.cs

@@ -0,0 +1,58 @@
+using System;
+using System.Numerics;
+using System.Collections.Generic;
+
+namespace bern
+{
+    class Program
+    {
+        struct BerNum { public int index; public BigInteger Numer, Denomin; };
+        static int w1 = 1, w2 = 1; // widths for formatting output
+        static int max = 60; // default maximum, can override on command line
+
+        // returns nth Bernoulli number
+        static BerNum CalcBernoulli(int n)
+        {
+            BerNum res;
+            BigInteger f;
+            BigInteger[] nu = new BigInteger[n + 1],
+                         de = new BigInteger[n + 1];
+            for (int m = 0; m <= n; m++)
+            {
+                nu[m] = 1; de[m] = m + 1;
+                for (int j = m; j > 0; j--)
+                    if ((f = BigInteger.GreatestCommonDivisor(
+                        nu[j - 1] = j * (de[j] * nu[j - 1] - de[j - 1] * nu[j]),
+                        de[j - 1] *= de[j])) != BigInteger.One)
+                    { nu[j - 1] /= f; de[j - 1] /= f; }
+            }
+            res.index = n; res.Numer = nu[0]; res.Denomin = de[0];
+            w1 = Math.Max(n.ToString().Length, w1);             // ratchet up widths
+            w2 = Math.Max(res.Numer.ToString().Length, w2);
+            if (max > 50) Console.Write("."); // progress dots appear for larger values
+            return res;
+        }
+
+        static void Main(string[] args)
+        {
+            List<BerNum> BNumbList = new List<BerNum>();
+            // defaults to 60 when no (or invalid) command line parameter is present
+            if (args.Length > 0) {
+                int.TryParse(args[0], out max);
+                if (max < 1 || max > Int16.MaxValue) max = 60;
+                if (args[0] == "0") max = 0;
+            }
+            for (int i = 0; i <= max; i++) // fill list with values
+            {
+                BerNum BNumb = CalcBernoulli(i);
+                if (BNumb.Numer != BigInteger.Zero) BNumbList.Add(BNumb);
+            }
+            if (max > 50) Console.WriteLine();
+            string strFmt = "B({0, " + w1.ToString() + "}) = {1, " + w2.ToString() + "} / {2}";
+            // display formatted list
+            foreach (BerNum bn in BNumbList)
+                Console.WriteLine(strFmt , bn.index, bn.Numer, bn.Denomin);
+            if (System.Diagnostics.Debugger.IsAttached) Console.Read();
+        }
+    }
+}