On Tue, 25 Jan 2022, Igor Zhuravlov wrote:

Just a remark: the sentence
 %"_1 _ +/&.:*:
finds column norms, then normalizes rows. To normalize columns the rank-
specifying part should be removed:
 % +/&.:*:

That is incorrect.  Example:

   ]x=. ?3 6$0                             NB.six 3-d vectors
0.622471 0.324707 0.907825 0.0631566  0.38662 0.338598
0.095767 0.601479 0.285658  0.926716 0.299674 0.417604
0.687686 0.837773 0.792088  0.465073 0.605581 0.190086
   (%"_1 _ +/&.:*:) x                      NB.normalize all
0.667531  0.30031 0.733179 0.0607982 0.496644  0.59378
0.102699 0.556287 0.230703  0.892111 0.384955  0.73233
0.737466 0.774828 0.639707  0.447706 0.777917 0.333344
   (% +/&.:*:) 0.622471 0.095767 0.687686  NB.manually check first column
0.66753 0.102699 0.737466
   (% +/&.:*:) x                           NB.try without rank
|length error
|       (%+/&.:*:)x


 -E
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