16 lines
589 B
Common Lisp
16 lines
589 B
Common Lisp
(defun running-std (items)
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(let ((running-sum 0)
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(running-len 0)
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(running-squared-sum 0)
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(result 0))
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(dolist (item items)
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(setq running-sum (+ running-sum item))
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(setq running-len (1+ running-len))
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(setq running-squared-sum (+ running-squared-sum (* item item)))
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(setq result (sqrt (- (/ running-squared-sum (float running-len))
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(/ (* running-sum running-sum)
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(float (* running-len running-len))))))
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(message "%f" result))
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result))
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(running-std '(2 4 4 4 5 5 7 9))
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