atan魔方陣 https://twitter.com/toku51n/status/1533401499983749121 をxyzzyで検証

verify.l

;;; https://github.com/TokusiN/AtanMagic/blob/main/data.txt を保存して開いておく

(labels ((read-data (buf)
           (with-input-from-buffer (buf)
             (loop for i to 15 collect
               (mapcar #'read-from-string (split-string (read-line) #\,)))))
         (frac2comp (f)
           (complex (denominator f) (numerator f)))
         (verify1 (desc row)
           ; 各分数を複素数に変換(p/q → q+pi)し、総乗の虚数部=0 かつ 偏角の総和≒2πならokとする
           (let* ((l (mapcar #'frac2comp row))
                  (p (reduce #'* l))
                  (sa (reduce #'+ (mapcar #'phase l)))
                  (ok? (and (integerp p) (< (abs (- (* 2 pi) sa)) 1d-2))))
             (format t "~a: ~:[ng~;ok~] Π=~a Σarg=~a~%" desc ok? p sa))))
  (let ((m (read-data "data.txt")))
    (dotimes (i 16)
      (verify1 (format nil "→~a" i) (nth i m))
      (verify1 (format nil "↓~a" i) (mapcar #'(lambda (l) (nth i l)) m)))
    (verify1 "＼" (loop for i to 15 collect (nth i (nth i m))))
    (verify1 "／" (loop for i to 15 collect (nth i (nth (- 15 i) m))))))

verify_result.txt

→0: ok Π=28574842746751575601507416152178564453125 Σarg=6.283186
↓0: ok Π=2694115124952777088420153901838049740625 Σarg=6.283186
→1: ok Π=74464444597257664886143740323293343400625 Σarg=6.283186
↓1: ok Π=244331023900548270790308342156217827265625 Σarg=6.283185
→2: ok Π=91787877424280097285579261111324768578125 Σarg=6.283185
↓2: ok Π=364485918036519778217822637356301522265625 Σarg=6.283185
→3: ok Π=280660894099274185616629426782072314453125 Σarg=6.283185
↓3: ok Π=241706671266656329004532084368076923828125 Σarg=6.283185
→4: ok Π=79519294177931557346182700515956494140625 Σarg=6.283185
↓4: ok Π=546562351379809417181962977879890470703125 Σarg=6.283185
→5: ok Π=105966135071751780025570301374408449453125 Σarg=6.283186
↓5: ok Π=226275128890363192997917128989381413765625 Σarg=6.283185
→6: ok Π=425804347376179249589620046122447819328125 Σarg=6.283185
↓6: ok Π=17199359902335431118176230016852821765625 Σarg=6.283185
→7: ok Π=241217124402603698239465659412103277258445 Σarg=6.283185
↓7: ok Π=168047129395669820160881121671245514290625 Σarg=6.283185
→8: ok Π=79050321573014280793667319528121133178125 Σarg=6.283185
↓8: ok Π=123548023376498407899624595839766038651125 Σarg=6.283185
→9: ok Π=1918110855783606257900218716027122332466645 Σarg=6.283185
↓9: ok Π=33704436567405880913801530294248211328125 Σarg=6.283185
→10: ok Π=163841908462292584575950644479837749420125 Σarg=6.283185
↓10: ok Π=273032439595378390134487522307330836765025 Σarg=6.283185
→11: ok Π=1828974110930840770989548972783410644548125 Σarg=6.283185
↓11: ok Π=57659909413055226192398145836043634765625 Σarg=6.283185
→12: ok Π=63561128035258205479830951212215392578125 Σarg=6.283185
↓12: ok Π=3851551823351160315433262808612362468517625 Σarg=6.283185
→13: ok Π=922685165201808988378548285425806328721325 Σarg=6.283186
↓13: ok Π=918150282112652671766964438607724542060625 Σarg=6.283185
→14: ok Π=5639674075902992860490627523432553891625 Σarg=6.283185
↓14: ok Π=76528524366980421689183052855011993498225 Σarg=6.283185
→15: ok Π=71123740457590194046628628858734072265625 Σarg=6.283185
↓15: ok Π=137883879499894706636993181864810004140625 Σarg=6.283186
＼: ok Π=878049202419008653353310688887703571240625 Σarg=6.283185
／: ok Π=135463329283292269552413400757187818453125 Σarg=6.283185