tindex ← {(⊂⊂⍺)⌷¨⍵}

   ⍪¨ 3 1 1 2 tindex T
┌──────┬───────┬─┬──┬────┐
│Wilson│Diana  │1│23│1.25│
│Jones │Dakota │1│29│0.97│
│Jones │Dakota │1│29│0.97│
│Chan  │Wilson │2│47│2.11│
└──────┴───────┴─┴──┴────┘

   ⍪¨ T
┌──────┬───────┬─┬──┬────┐
│Smith │John   │2│23│1.25│
│Jones │Dakota │1│29│0.97│
│Chan  │Wilson │2│47│2.11│
│Wilson│Diana  │1│23│1.25│
│Saxon │Joan   │1│31│2.8 │
│Angelo│Roberto│2│19│1.11│
│Smits │Jack   │2│27│3.14│
│Franck│Donna  │1│38│2.72│
└──────┴───────┴─┴──┴────┘