Various changes; see description

• Yr: if the first input is a vector of 2 elements it is automatically sorted

• Y" with 2 inputs: second input is linearized if needed. If the first or second input is shorter than the other, entries are repeated cyclically to match lengths

• The loop variable in the "do twice" loop now takes values 0 and 1, not F and T.

• Zv with two inputs: symmetrize array along specified dimension

• Zu now requires two inputs. Strings in second input can be replaced by numbers