12 lines
288 B
Scheme
12 lines
288 B
Scheme
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(define (forward-diff lst)
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(if (or (null? lst) (null? (cdr lst)))
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'()
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(cons (- (cadr lst) (car lst))
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(forward-diff (cdr lst)))))
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(define (nth-forward-diff n xs)
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(if (= n 0)
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xs
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(nth-forward-diff (- n 1)
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(forward-diff xs))))
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