Boolean algebra provides an important model for the description of knowledge using a binary language. This paper considers a multivalued language, based on arrays and co-arrays, that allows a multivalued description of the knowledge contained in a data table.
This multivalued algebra has some special elements which are arryas and co-arrays at the same time: the degenerate arrays. These degenerate arrays are singled out and their interpretation analyzed, which gives rise to the introduction of the array projections and co-array projections.
Finally, a relation between array projections, co-array projections and uncertain data tables is examined.