day of

day of is used to determine the day of the week on which a particular sample was taken.

For example, given the following case fragment,

           01 Jun 03    20 Jun 03    03 Sep 03    15 Oct 03    02 Nov 03
ABC           2.5          2.3          2.2          2.1          2.0
DEF           6.3                       4.0          1.9

day of second most recent ABC is “Wednesday”

day of max ABC is “Sunday”

day of most recent ABC is “Sunday”