Single column from many (containing blanks) (1) – Rows first 24

Given a two-dimensional array, potentially containing some empty cells, it is sometimes desirable to create a list of all non-blank entries from that array in a single column.

In general, it is not a major concern in which order the returns appear in this new column, and indeed the “standard” solution for this problem is the one given here, in which those returns are listed in an order which is consistent with the entries from an entire row from the original array being returned prior to moving onto those in the next row. The converse, in which entries are returned in a columns-first fashion, will be the subject of my first Advanced Formula Challenge post to follow this one.