TESTS2 ,: PRICES1 {~ BUCKETS1 (#...@[ <:@- |....@[ I. ]) TESTS2=:__ _9999
9999 _
__ _9999 9999 _
__ __ _ _
I assume this is what you want.
R.E. Boss
> -----Oorspronkelijk bericht-----
> Van: [email protected] [mailto:programming-
> [email protected]] Namens Dan Bron
> Verzonden: woensdag 17 maart 2010 20:33
> Aan: 'Programming forum'
> Onderwerp: Re: [Jprogramming] How to use dyad I.
>
> That looks good, but can't look at it right now -- does it appropriately
> give __ and _ for _9999 and 9999 respectively?
>
> -Dan
>
> -----Original Message-----
> From: [email protected] [mailto:programming-
> [email protected]] On Behalf Of R.E. Boss
> Sent: Wednesday, March 17, 2010 1:51 PM
> To: 'Programming forum'
> Subject: Re: [Jprogramming] How to use dyad I.
>
> If I slightly change your BUCKETS, PRICES and TESTS in
>
> BUCKETS1 =: __ , ge , {: lt
>
> PRICES1 =: __ , _ ,~ out
>
> TESTS1=: BUCKETS1 , _
>
> and use a verb which is equivalent to Schott's Idotr and Millers F, I get
>
> TESTS1 ,: PRICES1 {~ BUCKETS1 (#...@[ <:@- |....@[ I. ]) TESTS1
> __ 0 0.06 0.11 0.16 0.21 0.26 0.31 0.36 0.41 0.46 0.51 0.56 0.61 0.66
> 0.71
> 0.76 0.81 0.86 0.91 0.96 1.01 _
> __ 0.1 0.18 0.26 0.32 0.38 0.44 0.5 0.54 0.58 0.62 0.66 0.7 0.74 0.78
> 0.82
> 0.86 0.9 0.94 0.98 1 _ _
>
> Is this what you want?
>
>
> R.E. Boss
>
>
> > -----Oorspronkelijk bericht-----
> > Van: [email protected] [mailto:programming-
> > [email protected]] Namens Dan Bron
> > Verzonden: dinsdag 16 maart 2010 15:54
> > Aan: 'Programming forum'
> > Onderwerp: [Jprogramming] How to use dyad I.
> >
> > When using dyad I, how does one control how to handle the various edge
> > conditions gracefully (specifically out-of-bounds values and
> > values exactly between intervals)?
> >
> > (1) y is greater or lesser than the head or tail of x
> > (2) y is exactly equal to a value of x, and I want to
> > decide if that means it should fall to the left
> > of the value or to the right.
> >
> > All of this with an eye to performance, of course (I don't want to do
> the
> > equality outer product x=/y to handle edge conditions, for
> > example).
> >
> > For example, how would you solve
> > http://rosettacode.org/wiki/Price_Fraction cleanly? My first quick hack
> > is:
> >
> > 'ge lt out'=:ALL=:|: 0 ". ];._2 noun define
> > 0.00 0.06 0.1
> > 0.06 0.11 0.18
> > 0.11 0.16 0.26
> > 0.16 0.21 0.32
> > 0.21 0.26 0.38
> > 0.26 0.31 0.44
> > 0.31 0.36 0.5
> > 0.36 0.41 0.54
> > 0.41 0.46 0.58
> > 0.46 0.51 0.62
> > 0.51 0.56 0.66
> > 0.56 0.61 0.7
> > 0.61 0.66 0.74
> > 0.66 0.71 0.78
> > 0.71 0.76 0.82
> > 0.76 0.81 0.86
> > 0.81 0.86 0.9
> > 0.86 0.91 0.94
> > 0.91 0.96 0.98
> > 0.96 1.01 1
> > )
> >
> > NB. Price buckets; the infinities are sentinels allowing me
> > NB. to handle any unknown price.
> > BUCKETS =: __ , _ ,~ ge , {: lt
> >
> > NB. Test exactly at buckets, and well within buckets
> > TESTS =: _9999 9999 (1 _2) } }: , (,. _ ,~ 2 (+/%#)\])
> > BUCKETS
> >
> > NB. Low unknown prices = __ , high unknown = _ .
> > PRICES =: __ __ , _ ,~ out
> >
> > smoutput TESTS ,: PRICES {~ (_1e_16 + BUCKETS) I. TESTS
> >
> > (the handling of out-of-bounds values isn't required by the RC task, but
> > I'm just using the RC task to illustrate common issues I
> > have with I.)
> >
> > Reasons I don't like this hack (bearing in mind I didn't think much,
> just
> > wrote code until I got a solution that mostly worked):
> >
> > (a) It's still not right (for the input 1.01 the output
> > is 1, where it should be _),
> > (b) The addition of _1e_16 feels hacky and will break if
> > I. ever gets tolerant (or under various other conditions)
> > (c) I had to prepend 2 copies of __ to prices, instead of
> > 1, to get this to work.
> >
> > Also, I note that the Python solution leverages a function called
> > bisect.bisect_right -- implying there's a bisect.bisect_left. Is
> > I. inherently biased in one direction or the other, or is this managed
> by
> > using different grades or applying reversals?
> >
> > -Dan
> >
> >
> > ----------------------------------------------------------------------
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>
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