52 lines
1.2 KiB
Plaintext
52 lines
1.2 KiB
Plaintext
define stat1(a) => {
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if(#a->size) => {
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local(mean = (with n in #a sum #n) / #a->size)
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local(sdev = math_pow(((with n in #a sum Math_Pow((#n - #mean),2)) / #a->size),0.5))
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return (:#sdev, #mean)
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else
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return (:0,0)
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}
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}
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define stat2(a) => {
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if(#a->size) => {
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local(sx = 0, sxx = 0)
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with x in #a do => {
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#sx += #x
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#sxx += #x*#x
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}
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local(sdev = math_pow((#a->size * #sxx - #sx * #sx),0.5) / #a->size)
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return (:#sdev, #sx / #a->size)
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else
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return (:0,0)
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}
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}
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define histogram(a) => {
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local(
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out = '\r',
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h = array(0,0,0,0,0,0,0,0,0,0,0),
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maxwidth = 50,
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sc = 0
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)
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with n in #a do => {
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#h->get(integer(#n*10)+1) += 1
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}
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local(mx = decimal(with n in #h max #n))
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with i in #h do => {
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#out->append((#sc/10.0)->asString(-precision=1)+': '+('+' * integer(#i / #mx * #maxwidth))+'\r')
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#sc++
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}
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return #out
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}
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with scale in array(100,1000,10000,100000) do => {^
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local(n = array)
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loop(#scale) => { #n->insert(decimal_random) }
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local(sdev1,mean1) = stat1(#n)
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local(sdev2,mean2) = stat2(#n)
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#scale' numbers:\r'
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'Naive method: sd: '+#sdev1+', mean: '+#mean1+'\r'
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'Second method: sd: '+#sdev2+', mean: '+#mean2+'\r'
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histogram(#n)
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'\r\r'
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^}
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