GNU APL's domino gives a domain error for matrices that are close to
singular, but aren't.

      )clear
CLEAR WS

      A←100 100⍴101↑1
      A[1;1]←0

[IBM APL2]

       10 10 ↑⌹A+⎕CT×100
 1.000000001E11 ¯1 ¯1 ¯1 ¯1 ¯1 ¯1 ¯1 ¯1 ¯1
¯1.000000000E0   1  0  0  0  0  0  0  0  0
¯1.000000000E0   0  1  0  0  0  0  0  0  0
¯1.000000000E0   0  0  1  0  0  0  0  0  0
¯1.000000000E0   0  0  0  1  0  0  0  0  0
¯1.000000000E0   0  0  0  0  1  0  0  0  0
¯1.000000000E0   0  0  0  0  0  1  0  0  0
¯1.000000000E0   0  0  0  0  0  0  1  0  0
¯1.000000000E0   0  0  0  0  0  0  0  1  0
¯1.000000000E0   0  0  0  0  0  0  0  0  1

[GNU APL]

      10 10 ↑⌹A+⎕CT×100
DOMAIN ERROR
      10 10↑⌹A+⎕CT×100
            ^^

A matrix whose determinant is 1E¯11 is obviously not singular.

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