28 lines
555 B
Text
28 lines
555 B
Text
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(lib 'list)
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(lib 'matrix)
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;; adapted from Racket
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(define (permanent M)
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(let (( n (matrix-row-num M)))
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(for/sum ([σ (in-permutations n)])
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(for/product ([i n] [σi σ])
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(array-ref M i σi)))))
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;; output
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(define A (list->array '(1 2 3 4) 2 2))
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(array-print A)
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1 2
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3 4
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(determinant A) → -2
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(permanent A) → 10
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(define M (list->array (iota 25) 5 5))
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(array-print M)
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0 1 2 3 4
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5 6 7 8 9
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10 11 12 13 14
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15 16 17 18 19
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20 21 22 23 24
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(determinant M) → 0
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(permanent M) → 6778800
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