Cumulative standard deviation
editable example
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ghul
use IO.Std.write_line
use System.Math.sqrt
let standard_deviation =
let count mut = 0 in
let total mut = 0.0D in
let squares mut = 0.0D in
(sample: double) -> double => (
count = count + 1
total = total + sample
squares = squares + sample * sample
let mean = total / cast double(count)
sqrt(squares / cast double(count) - mean * mean)
)
for sample in [2.0D, 4.0D, 4.0D, 4.0D, 5.0D, 5.0D, 7.0D, 9.0D] do
write_line("after {sample}: {standard_deviation(sample)}")
od