PrimitiveDataFrameColumnComputations produce wrong result for Min/Max functions

[0xcafebabee]

System information

• OS version/distro: Windows 10
• .NET Version (eg., dotnet --info): netstandard2.0

Issue

Microsoft.Data.Analysis\PrimitiveDataFrameColumnComputations.cs provide wrong result for Min/Max functions

For these functions (and probably some other) we have wrong computation results:

We start computing from default value (code produced from tt templates):

Default value for integer is 0 and on each iteration we set 0 to ret not regarding that I have (for example) only positive values in column container:

public void Min(PrimitiveColumnContainer column, IEnumerable rows, out int ret)
{
ret = default;
var readOnlySpan = column.Buffers[0].ReadOnlySpan;
long minRange = 0;
long maxRange = ReadOnlyDataFrameBuffer.MaxCapacity;
long maxCapacity = maxRange;
IEnumerator enumerator = rows.GetEnumerator();
while (enumerator.MoveNext())
{
long row = enumerator.Current;
if (row < minRange || row >= maxRange)
{
int bufferIndex = (int)(row / maxCapacity);
readOnlySpan = column.Buffers[bufferIndex].ReadOnlySpan;
minRange = checked(bufferIndex * maxCapacity);
maxRange = checked((bufferIndex + 1) * maxCapacity);
}
row -= minRange;
ret = (int)(Math.Min(readOnlySpan[(int)row], ret));
}
}

As a result I have ret = 0. The same case is in Max function if I have only negative values in readOnlySpan collection.

[ericstj]

cc @pgovind @eerhardt

[asmirnov82]

Hello @luisquintanilla, looks like this issues is already fixed by #6147 and may be closed