private static bool VerifyVectorColumnsMatch(int cachedSize, int col, IDataView dv,
ColumnType type, ref VBuffer <DvText> firstDvSlotNames)
{
if (cachedSize != type.VectorSize)
{
return(false);
}
// If we detect mismatch it a sign that slots reshuffling has happened.
if (dv.Schema.HasSlotNames(col, type.VectorSize))
{
// Verify that slots match with slots from 1st idv.
VBuffer <DvText> currSlotNames = default(VBuffer <DvText>);
dv.Schema.GetMetadata(MetadataUtils.Kinds.SlotNames, col, ref currSlotNames);
if (currSlotNames.Length != firstDvSlotNames.Length)
{
return(false);
}
else
{
var result = true;
VBufferUtils.ForEachEitherDefined(ref currSlotNames, ref firstDvSlotNames,
(slot, val1, val2) => result = result && DvText.Identical(val1, val2));
return(result);
}
}
else
{
// If we don't have slot names, then the first dataview should not have had slot names either.
return(firstDvSlotNames.Length == 0);
}
}
/// <summary>
/// Computes the L1 distance between two VBuffers
/// </summary>
/// <param name="a">one VBuffer</param>
/// <param name="b">another VBuffer</param>
/// <returns>L1 Distance from a to b</returns>
public static Float L1Distance(ref VBuffer <Float> a, ref VBuffer <Float> b)
{
Float res = 0;
VBufferUtils.ForEachEitherDefined(ref a, ref b,
(slot, val1, val2) => res += Math.Abs(val1 - val2));
return(res);
}