a # 1 60 R ' rowform;r                                                  '
a # a,[1]  ' $0 if 0=(RRa)XRRb                                          '
a # a,[1]  ' a#(r,1URa)Ya H b#((r#(1YRa)S1YRb),1URb)Yb                  '
a # a,[1]  ' $0                                                         '
a # a,[1]  '"rowform is used by e.g. ccat.                              '
a # a,[1]  '"from ''the apl handbook of techniques'' copyright 1978, ibm. '
a # a,[1]  '"assumes localized a and b.                                 '
Lfx a