Casio ALGEBRA FX 2.0 Manual page 8

Descending order
Use the same procedure as that for the ascending order sort. The only difference is that
you should press c(SortD) in place of b(SortA).
# You can specify a value from 1 to 6 as the
number of lists for sorting.
# If you specify a list more than once for a single
sort operation, an error occurs.
An error also occurs if lists specified for sorting
do not have the same number of values (rows).
3-1-7
Inputting and Editing a List
# Specifying a value of 0 for the number of lists
causes all the lists in the file to be sorted. In
this case you specify a base list on which all
other lists in the file are sorted.
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