DataFrame should support Array data

[pgovind]

Currently, DataFrame only supports primitive types. Specifically, a DataFrameColumn can only only 1 primitive value per row. There are applications however that need to hold a DataFrameColumn of Array<T>, so each row holds an array of values. ML.NET supports holding Array, so IDataView.ToDataFrame might run into this issue at some point.

[LittleLittleCloud]

Thanks for bring this up

[rosebyte]

Array-like ML.NET data is now represented by VBufferDataFrameColumn<T>, which stores a vector for each row and supports IDataView conversion.