[Jprogramming] Using the hypergeometric adverb (H.).

[Raul Miller]

Here is one approach:

Mn=: 13 :'y H.(-x+1e_7)2'"1
M=:  13 :'|:y Mn 1 2 3,&>/-i.1+y'
ms=. 13 : '(<:a),:%:a*(+:b)->:a[''a b''=.|:2%~/\"1 M y'

I'm not sure if that helps...

(I am also slightly dubious about that whole +1e_7 epsilon thing.)

-- 
Raul


On Thu, Jul 7, 2016 at 4:53 PM, 'Bo Jacoby' via Programming
<programming at jsoftware.com> wrote:
> I am estimating the number of known answers (x) in a multiple choice test, knowing the number of correctly  (y) and incorrectly  (n-y) answered questions.
> The computation shows that N=10 and y=8 gives x=5±2.
> I would like to compress the three lines defining M0, M1 and M2 into at single line.
> Thank you!
> Bo.
>      M0=. 13 : '(1,-x)H.(-y+1e_7)2'
>
>      M1=. 13 : '(2,-x)H.(-y+1e_7)2'
>      M2=. 13 : '(3,-x)H.(-y+1e_7)2'
>      M =. 13 : '>(i.>:y)(M0,M1,M2)&.>y'
>      ms=. 13 : '(<:a),:%:a*(+:b)->:a[''a b''=.|:2%~/\"1 M y'
>      3":(i.@>:,ms) 10
>  0 1 2 3 4 5 6 7 8 9 10
>  0 0 0 1 1 2 3 4 5 7 9
> 0 0 1 1 1 1 2 2 2 2 1
> ----------------------------------------------------------------------
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