Thank you very much, Raul. It works!
I agree that (+1e_7) makes the result slightly incorrect, but omitting it makes
the result hugely incorrect. I suspect that it avoids a bug in (H.).
(1 _10 H. _10)2
_
(1 _10 H. _10.000001)2
2047
Thanks.
Bo.
Den 23:47 torsdag den 7. juli 2016 skrev Raul Miller
<[email protected]>:
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
<[email protected]> 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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