| public static IntToPrefixCodedBytes ( int val, int shift, BytesRef bytes ) : void | ||
| val | int | the numeric value |
| shift | int | how many bits to strip from the right |
| bytes | BytesRef | will contain the encoded value |
| return | void | |
public virtual void TestIntSpecialValues()
{
int[] vals = new int[] { int.MinValue, int.MinValue + 1, int.MinValue + 2, -64765767, -4000, -3000, -2000, -1000, -1, 0, 1, 10, 300, 765878989, int.MaxValue - 2, int.MaxValue - 1, int.MaxValue };
BytesRef[] prefixVals = new BytesRef[vals.Length];
for (int i = 0; i < vals.Length; i++)
{
prefixVals[i] = new BytesRef(NumericUtils.BUF_SIZE_INT);
NumericUtils.IntToPrefixCodedBytes(vals[i], 0, prefixVals[i]);
// check forward and back conversion
Assert.AreEqual(vals[i], NumericUtils.PrefixCodedToInt(prefixVals[i]), "forward and back conversion should generate same int");
// test if decoding values as long fails correctly
try
{
NumericUtils.PrefixCodedToLong(prefixVals[i]);
Assert.Fail("decoding a prefix coded int value as long should fail");
}
catch (FormatException e)
{
// worked
}
}
// check sort order (prefixVals should be ascending)
for (int i = 1; i < prefixVals.Length; i++)
{
Assert.IsTrue(prefixVals[i - 1].CompareTo(prefixVals[i]) < 0, "check sort order");
}
// check the prefix encoding, lower precision should have the difference to original value equal to the lower removed bits
BytesRef @ref = new BytesRef(NumericUtils.BUF_SIZE_LONG);
for (int i = 0; i < vals.Length; i++)
{
for (int j = 0; j < 32; j++)
{
NumericUtils.IntToPrefixCodedBytes(vals[i], j, @ref);
int prefixVal = NumericUtils.PrefixCodedToInt(@ref);
int mask = (1 << j) - 1;
Assert.AreEqual(vals[i] & mask, vals[i] - prefixVal, "difference between prefix val and original value for " + vals[i] + " with shift=" + j);
}
}
}
public virtual void TestIntConversionAndOrdering()
{
// generate a series of encoded ints, each numerical one bigger than the one before
BytesRef last = null, act = new BytesRef(NumericUtils.BUF_SIZE_INT);
for (int i = -100000; i < 100000; i++)
{
NumericUtils.IntToPrefixCodedBytes(i, 0, act);
if (last != null)
{
// test if smaller
Assert.IsTrue(last.CompareTo(act) < 0, "actual bigger than last (BytesRef)");
//Assert.IsTrue(last.Utf8ToString().CompareTo(act.Utf8ToString()) < 0, "actual bigger than last (as String)");
}
// test is back and forward conversion works
Assert.AreEqual(i, NumericUtils.PrefixCodedToInt(act), "forward and back conversion should generate same int");
// next step
last = act;
act = new BytesRef(NumericUtils.BUF_SIZE_INT);
}
}
