private void Test50Choose25()
{
// This function tests out the long binomial coefficien class for the case 50 choose 25.
//
// Test out the unsigned long version of GetBinCoeff. The int version overflows.
int n = 50;
int k = 25;
// Create the BinCoeff object that will be used for all the tests for the 50 choose 25 case.
BCL = new BinCoeffL(n, k);
ulong NumCombos50Choose25 = BCL.GetNumCombos(n, k);
if (NumCombos50Choose25 != 126410606437752)
{
string s = "Test50Choose25: GetNumCombos did not calculate the correct value for 50 choose 25.";
DisplayMsg(s);
return;
}
try
{
VerifyTranslastion50Choose25();
}
catch
{
DisplayMsg("Test50Choose25: did not complete successfully.");
return;
}
DisplayMsg("Test50Choose25: completed successfully.");
}
private ulong BenchmarkBCNumCombos2(int n, int k, out long ticks)
{
// This method benchmarks getting the number of combos for this n choose k case, including the constructor.
//
ulong numCombos;
GC.Collect();
Stopwatch sw = Stopwatch.StartNew();
var bc = new BinCoeffL(n, k);
numCombos = bc.GetNumCombos();
sw.Stop();
ticks = sw.ElapsedTicks;
return(numCombos);
}
private void Test100Choose95SubCases()
{
// This method tests out the new int functionality of specifying a lower n choose k case without having to
// create a new version of Pascal's Triangle to handle it. This version checks the 100 choose 95 case.
//
string s;
bool overflow;
int n = 100, k = 95, kLoop;
BinCoeffL bcl = new BinCoeffL(n, k);
ulong numCombos, numCombos2, rank, highRank;
uint rankLoop;
int[] kIndexes = new int[k];
// Test all subcases of 100 choose 95.
for (kLoop = k; kLoop > 0; kLoop--)
{
numCombos = bcl.GetNumCombos(n, kLoop);
numCombos2 = BinCoeffBase.GetCombosCount(n, kLoop);
if (numCombos != numCombos2)
{
s = $"Test100Choose95SubCases: Error - {n} choose {k}: # of combos does not match.";
Console.WriteLine(s);
return;
}
// Test the lowest 10 ranks and the highest 10 ranks for each subcase test case.
for (rankLoop = 1; rankLoop <= 10; rankLoop++)
{
bcl.GetCombFromRank(rankLoop, kIndexes, n, kLoop);
rank = bcl.GetRank(true, kIndexes, out overflow, kLoop);
if (rank != rankLoop)
{
s = $"Test100Choose95SubCases: Error - {n} choose {kLoop}: rank or combo is wrong.";
Console.WriteLine(s);
return;
}
highRank = numCombos - rankLoop;
bcl.GetCombFromRank(highRank, kIndexes, n, kLoop);
rank = bcl.GetRank(true, kIndexes, out overflow, kLoop);
if (rank != highRank)
{
s = $"Test100Choose95SubCases: Error - {n} choose {kLoop}: high rank or combo is wrong.";
Console.WriteLine(s);
return;
}
}
}
}
private void BenchmarkBinCoeffMultiple(int[] numElemArray, int[] numGroupArray)
{
// This method benchmarks the n choose k tests for many subcases & ranks, and compares the performance against the Combination class methods.
// The first benchmark compares the performance of single methods. This one attempts a more "real-life" analysis and calls GetRank and
// GetComboFromRank 1,000 times for all the subcases for each test case.
//
int numItems, groupSize, caseLoop;
int[] kIndexes = new int[40];
ulong rankSum = 0;
int kLoop;
bool overflow;
BinCoeffL bcl;
long ticks, ticksAlt, ticksSum = 0, ticksSumAlt = 0;
ulong numCombos, rank, startRank, endRank, rankCount = 1000, rankLoop;
double d;
Stopwatch sw;
// Benchmark all the subcases.
for (caseLoop = 0; caseLoop < numElemArray.Length; caseLoop++)
{
GC.Collect();
sw = Stopwatch.StartNew();
numItems = numElemArray[caseLoop];
groupSize = numGroupArray[caseLoop];
bcl = new BinCoeffL(numItems, groupSize);
for (kLoop = groupSize; kLoop > 0; kLoop--)
{
numCombos = bcl.GetNumCombos(numItems, kLoop);
rankSum += numCombos;
startRank = (numCombos / 2) - 500;
endRank = startRank + rankCount;
for (rankLoop = startRank; rankLoop < endRank; rankLoop++)
{
bcl.GetCombFromRank(rankLoop, kIndexes, numItems, kLoop);
rank = bcl.GetRank(true, kIndexes, out overflow, kLoop);
rankSum += rank;
}
}
sw.Stop();
// Looking at the sum of the return values makes sure that the compiler does not optimize the code away.
if (rankSum == 0)
{
Console.WriteLine("Error - rankSum = 0?");
}
ticks = sw.ElapsedTicks;
//
// Benchmark the uint BinCoeff class subcases for 30 choose 15.
rankSum = 0;
sw = Stopwatch.StartNew();
for (kLoop = groupSize; kLoop > 4; kLoop--)
{
numCombos = Combination.GetNumCombos(numItems, kLoop);
rankSum += numCombos;
startRank = (numCombos / 2) - 500;
endRank = startRank + rankCount;
for (rankLoop = startRank; rankLoop < endRank; rankLoop++)
{
Combination.GetCombFromRankLong(rankLoop, kIndexes, numItems, kLoop);
rank = Combination.GetRank(kIndexes, out overflow, numItems, kLoop);
rankSum += rank;
}
}
sw.Stop();
ticksAlt = sw.ElapsedTicks;
// Display the results.
d = (double)ticksAlt / (double)ticks;
d = Math.Round(d, 2);
Console.WriteLine($"Multiple methods benchmark for {numItems} choose {groupSize} & subcases .vs. Combination class ratio = {d} to 1.");
ticksSum += ticks;
ticksSumAlt += ticksAlt;
}
d = (double)ticksSumAlt / (double)ticksSum;
d = Math.Round(d, 2);
Console.WriteLine($"Average for all n choose k cases & subcases .vs. Combination class ratio = {d} to 1.");
Console.WriteLine();
// Looking at the sum of the return values makes sure that the compiler does not optimize the code away.
if (rankSum == 0)
{
Console.WriteLine("Error - rankSum = 0?");
}
}
private TestResult TestLongSubCases(int n, int k)
{
// This method tests out the new int functionality of specifying a lower n choose k case without having to
// create a new version of Pascal's Triangle to handle it. n & k specifies the main n choose k case.
//
string s;
int nLoop, kLoop;
BinCoeffL bcl = new BinCoeffL(n, k);
ulong numCombos, numCombos2, rank, rankHigh, rank2, rankLoop;
int[] kIndexes = new int[k];
// If the # of combos overflowed, then don't try this case with uint.
if (bcl.TotalCombos == 0)
{
return(TestResult.IntOverflow);
}
// Try getting the rank and combination for all subcases of n choose k.
for (kLoop = k; kLoop > 0; kLoop--)
{
for (nLoop = n; nLoop >= kLoop; nLoop--)
{
numCombos = bcl.GetNumCombos(nLoop, kLoop);
numCombos2 = (uint)BinCoeffBase.GetCombosCount(nLoop, kLoop);
if (numCombos != numCombos2)
{
s = $"TestIntSubCases: Error - {n} choose {k}: # of combos does not match.";
Console.WriteLine(s);
return(TestResult.Failed);
}
ulong comboCount = numCombos;
// Loop thru all the combinations for this n choose k case if # of combos <= 1000.
// Otherwise, just do the lowest ranked 500 and the highest ranked 500.
if (numCombos > 1000)
{
comboCount = 500;
}
// Loop thru the combinations for this n choose k case.
for (rankLoop = 0; rankLoop < comboCount; rankLoop++)
{
bcl.GetCombFromRank(rankLoop, kIndexes, nLoop, kLoop);
rank = bcl.GetRank(true, kIndexes, out bool overflow, kLoop);
if (rank != rankLoop)
{
s = $"TestIntSubCases: Error - {n} choose {k}: rank or combo is wrong.";
Console.WriteLine(s);
return(TestResult.Failed);
}
// If not doing all the combinations, then process the high ranks.
if (numCombos > comboCount)
{
rankHigh = numCombos - rankLoop - 1;
// Get the k-indexes for this combination.
bcl.GetCombFromRank(rankHigh, kIndexes, nLoop, kLoop);
// Verify that the Kindexes returned can be used to retrieve the rank of the combination.
rank2 = bcl.GetRank(true, kIndexes, out overflow, kLoop);
if (rank2 != rankHigh)
{
s = $"TestIntSubCases: Error - {n} choose {k}: GetRank or GetCombFromRank failed - {rank2} != rankHigh at {rankLoop}";
Console.WriteLine(s);
return(TestResult.Failed);
}
}
}
}
}
return(TestResult.Passed);
}