public void NextFloatTest()
{
void Test(Random random, float min, float max)
{
for (FloatScale scale = 0; scale <= FloatScale.ForceLogarithmic; scale++)
{
Console.Write($@"Random float {min.ToRoundtripString()}..{max.ToRoundtripString()} {scale}: ");
float result;
try
{
result = random.NextSingle(min, max, scale);
Console.WriteLine(result.ToRoundtripString());
}
catch (Exception e)
{
Console.WriteLine($@"{e.GetType().Name}: {e.Message}".Replace(Environment.NewLine, " "));
throw;
}
Assert.IsTrue(result >= min && result <= max);
}
}
var rnd = new Random();
Test(rnd, Single.MinValue, Single.MaxValue);
Test(rnd, 0, Single.Epsilon);
Test(rnd, Single.MaxValue, Single.PositiveInfinity);
Test(rnd, Single.NegativeInfinity, Single.PositiveInfinity);
}
public void NextDoubleTest()
{
void Test(Random random, double min, double max)
{
for (FloatScale scale = 0; scale <= FloatScale.ForceLogarithmic; scale++)
{
Console.Write($@"Random double {min.ToRoundtripString()}..{max.ToRoundtripString()} ({scale}): ");
double result;
try
{
result = random.NextDouble(min, max, scale);
Console.WriteLine(result.ToRoundtripString());
}
catch (Exception e)
{
Console.WriteLine($@"{e.GetType().Name}: {e.Message}".Replace(Environment.NewLine, " "));
throw;
}
Assert.IsTrue(result >= min && result <= max);
}
}
var rnd = new Random();
// edge cases
Test(rnd, Double.MinValue, Double.MaxValue);
Test(rnd, Double.NegativeInfinity, Double.PositiveInfinity);
Test(rnd, 0, Double.PositiveInfinity);
Test(rnd, Double.MaxValue, Double.PositiveInfinity);
Test(rnd, Double.NegativeInfinity, Double.MinValue);
Test(rnd, 1.7976931348623155E+308, Double.MaxValue);
Throws <ArgumentOutOfRangeException>(() => Test(rnd, Double.PositiveInfinity, Double.PositiveInfinity));
Throws <ArgumentOutOfRangeException>(() => Test(rnd, Double.NegativeInfinity, Double.NegativeInfinity));
Throws <ArgumentOutOfRangeException>(() => Test(rnd, 0, Double.NaN));
Test(rnd, 0, Double.Epsilon);
Test(rnd, Double.Epsilon, Double.Epsilon * 4);
Test(rnd, Double.MaxValue / 4, Double.MaxValue);
Test(rnd, Double.MaxValue / 2, Double.MaxValue);
Test(rnd, -Double.Epsilon, Double.Epsilon);
Test(rnd, 0.000000001, 0.0000000011);
Test(rnd, 10000, 11000);
// big range
Test(rnd, Int64.MinValue, Int64.MaxValue);
Test(rnd, Int64.MinValue, 0);
Test(rnd, Int64.MaxValue, float.MaxValue);
Test(rnd, -0.1, UInt64.MaxValue); // very imbalanced positive-negative ranges
Test(rnd, 1L << 52, (1L << 54) + 10); // narrow exponent range
Test(rnd, Int64.MaxValue, (double)Int64.MaxValue * 4 + 10000); // small exponent range
Test(rnd, (double)Int64.MaxValue * 1024, (double)Int64.MaxValue * 4100); // small exponent range
Test(rnd, (double)Int64.MinValue * 4100, (double)Int64.MinValue * 1024); // small exponent range
// small range
Test(rnd, Int64.MaxValue, (double)Int64.MaxValue * 4);
Test(rnd, Int64.MaxValue, (double)Int64.MaxValue * 4 + 1000);
Test(rnd, 1L << 53, (1L << 53) + 2);
Test(rnd, 1L << 52, 1L << 53);
}
public void NextDecimalTest()
{
var rnd = new Random();
void Test(decimal min, decimal max)
{
for (FloatScale scale = 0; scale <= FloatScale.ForceLogarithmic; scale++)
{
Console.Write($@"Random decimal {min.ToRoundtripString()}..{max.ToRoundtripString()} ({scale}): ");
decimal result;
try
{
result = rnd.NextDecimal(min, max, scale);
Console.WriteLine(result.ToRoundtripString());
}
catch (Exception e)
{
Console.WriteLine($@"{e.GetType().Name}: {e.Message}".Replace(Environment.NewLine, " "));
throw;
}
Assert.IsTrue(result >= min && result <= max);
}
}
// edge cases
Test(Decimal.MinValue, Decimal.MaxValue);
Test(0, Decimal.MaxValue);
Test(0, DecimalExtensions.Epsilon);
Test(DecimalExtensions.Epsilon, DecimalExtensions.Epsilon * 4);
Test(Decimal.MaxValue / 2, Decimal.MaxValue);
Test(Decimal.MaxValue - 1, Decimal.MaxValue);
Test(Decimal.MaxValue - DecimalExtensions.Epsilon, Decimal.MaxValue);
Test(-DecimalExtensions.Epsilon, DecimalExtensions.Epsilon);
Test(0.000000001m, 0.0000000011m);
Test(10000, 11000);
// big range
Test(Int64.MinValue, Int64.MaxValue);
Test(Int64.MinValue, 0);
Test(-0.1m, UInt64.MaxValue); // very imbalanced positive-negative ranges
Test(1L << 52, (1L << 54) + 10); // narrow exponent range
Test(Int64.MaxValue, (decimal)Int64.MaxValue * 4 + 10000); // small exponent range
Test((decimal)Int64.MaxValue * 1024, (decimal)Int64.MaxValue * 4100); // small exponent range
Test((decimal)Int64.MinValue * 4100, (decimal)Int64.MinValue * 1024); // small exponent range
// small range
Test(Int64.MaxValue, (decimal)Int64.MaxValue * 4);
Test(Int64.MaxValue, (decimal)Int64.MaxValue * 4 + 1000);
Test(1L << 53, (1L << 53) + 2);
Test(1L << 52, 1L << 53);
}
