Matrix Inverse 2 Index   <<   >>

 
   ⎕rl←6*5    ⍝ for reproducible random numbers
   X←¯10+?6 6⍴25

   ¯3 ⍕ X +.× ⌹X
  1.00E0    3.55E¯15 ¯2.84E¯14 ¯1.78E¯14  2.49E¯14 ¯2.22E¯15
  5.55E¯17  1.00E0    2.84E¯14  2.13E¯14 ¯7.11E¯15  0.00E0  
 ¯6.94E¯17  3.55E¯15  1.00E0   ¯2.13E¯14  2.13E¯14  2.11E¯15
  2.78E¯17  3.55E¯15  7.11E¯15  1.00E0    0.00E0   ¯8.88E¯16
 ¯1.39E¯16 ¯1.07E¯14 ¯1.42E¯14  1.42E¯14  1.00E0    8.88E¯16
  3.47E¯16 ¯9.77E¯15 ¯1.78E¯14  2.13E¯14 ¯2.31E¯14  1.00E0  

   A← qi X
   ⍕Q A (+Q).(×Q) ⌹Q A
1 0 0 0 0 0
0 1 0 0 0 0
0 0 1 0 0 0
0 0 0 1 0 0
0 0 0 0 1 0
0 0 0 0 0 1