9 lines
375 B
Text
9 lines
375 B
Text
mean=: +/ % #
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dev=: - mean
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stddevP=: [: %:@mean *:@dev NB. A) 3 equivalent defs for stddevP
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stddevP=: [: mean&.:*: dev NB. B) uses Under (&.:) to apply inverse of *: after mean
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stddevP=: %:@(mean@:*: - *:@mean) NB. C) sqrt of ((mean of squares) - (square of mean))
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stddevP\ 2 4 4 4 5 5 7 9
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0 1 0.942809 0.866025 0.979796 1 1.39971 2
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