I finished coding this. I was disappointed to discover that when assigning an array to a column with dot notation, the data type has to match just like the SetItem function. The Any type only works for strings. I had to add code to copy the string array to an array of the correct type.

Hi, Roland - 

Have you tried something along the lines of:

Long li_startrow = 1, li_endrow = 5, li_colnumber = 3
String ls_values[5] = {"Alpha","Beta","Charlie","Dog","Edward"}

dw_1.Object.Data[li_startrow,li_colnumber,li_endrow,li_colnumber] = ls_values

According to the DW Reference publication/documentation, this should work.

4.2.1.2 Getting and storing the data from a DataWindow data expression
A DataWindow data expression can return a large amount of data.
Data structures for data
Single row and column
When your data expression refers to a single row and column, you can assign the data to a
variable whose data matches the column's datatype. When the expression refers to a single
column but can refer to multiple rows, you must specify an array of the appropriate datatype.

ldwo.data = ls_ColumnArray[]  should work

I used to use that data setting notation for some heavy processing in a report writer (copy from and to datastore/arrays)  .

But it was not compatible with an older version of powerserver so i had to change back to loops.

use the column number as in john's example ( that way you don't have to use the unsupported __get_attribute )