private static void TstDecodeAllPrev(long[] values, EliasFanoDecoder efd)
{
efd.ToAfterSequence();
for (int i = values.Length - 1; i >= 0; i--)
{
long previousValue = efd.PreviousValue();
Assert.IsFalse(EliasFanoDecoder.NO_MORE_VALUES == previousValue, "previousValue at end too early");
Assert.AreEqual(values[i], previousValue);
}
Assert.AreEqual(EliasFanoDecoder.NO_MORE_VALUES, efd.PreviousValue());
}
private static void TstDecodeBackToMultiples(long[] values, EliasFanoDecoder efd, long m)
{
// test backing to multiples of m
Debug.Assert(m > 0);
efd.ToAfterSequence();
int index = values.Length - 1;
if (index < 0)
{
long advanceValue = efd.BackToValue(0);
Assert.AreEqual(EliasFanoDecoder.NO_MORE_VALUES, advanceValue);
return; // empty values, nothing to go back to/from
}
long expValue = values[index];
long previousValue = expValue + 1;
long mm = (expValue / m) * m;
while (index >= 0)
{
expValue = values[index];
Debug.Assert(mm < previousValue);
if (expValue <= mm)
{
long backValue_ = efd.BackToValue(mm);
Assert.IsFalse(EliasFanoDecoder.NO_MORE_VALUES == backValue_, "backToValue at end too early");
Assert.AreEqual(expValue, backValue_);
Assert.AreEqual(index, efd.CurrentIndex());
previousValue = expValue;
do
{
mm -= m;
} while (mm >= previousValue);
}
index--;
}
long backValue = efd.BackToValue(mm);
Assert.AreEqual(EliasFanoDecoder.NO_MORE_VALUES, backValue);
}
private static void TstDecodeBackToMultiples(long[] values, EliasFanoDecoder efd, long m)
{
// test backing to multiples of m
Debug.Assert(m > 0);
efd.ToAfterSequence();
int index = values.Length - 1;
if (index < 0)
{
long advanceValue = efd.BackToValue(0);
Assert.AreEqual(EliasFanoDecoder.NO_MORE_VALUES, advanceValue);
return; // empty values, nothing to go back to/from
}
long expValue = values[index];
long previousValue = expValue + 1;
long mm = (expValue / m) * m;
while (index >= 0)
{
expValue = values[index];
Debug.Assert(mm < previousValue);
if (expValue <= mm)
{
long backValue_ = efd.BackToValue(mm);
Assert.IsFalse(EliasFanoDecoder.NO_MORE_VALUES == backValue_, "backToValue at end too early");
Assert.AreEqual(expValue, backValue_);
Assert.AreEqual(index, efd.CurrentIndex());
previousValue = expValue;
do
{
mm -= m;
} while (mm >= previousValue);
}
index--;
}
long backValue = efd.BackToValue(mm);
Assert.AreEqual(EliasFanoDecoder.NO_MORE_VALUES, backValue);
}
