Thanks for the good ideas (though first post goes to Mr. Boss, not Raul).
On Mon, Jan 5, 2015 at 11:36 AM, 'Pascal Jasmin' via Programming <
[email protected]> wrote:
> as a single more general function
>
> a: ;@:(] <@(# # {. );.1~ 1 (0}) -.@=
> )'';'Hi';'';'';'Ho';'';'hee';'';'';'haw';'';'';'Yo';''
>
>
> 0 ;@:(] <@(# # {. );.1~ 1 (0}) -.@= ) 0 33 0 0 22 0 0 11 0 0 0
> 0 33 33 33 22 22 22 11 11 11 11
>
>
>
> ----- Original Message -----
> From: 'Pascal Jasmin' via Programming <[email protected]>
> To: "[email protected]" <[email protected]>
> Cc:
> Sent: Monday, January 5, 2015 11:26 AM
> Subject: Re: [Jprogramming] Forward fill w/o looping
>
> dyadic ;. is your usual friend in these cases. Though Raul has often
> found even more elegant approaches.
>
> a: (-.@= <;.1 ] )'Hi';'';'';'Ho';'';'hee';'';'';'haw';'';'';'Yo';''
> ┌──────┬─────┬───────┬───────┬─────┐
> │┌──┬┬┐│┌──┬┐│┌───┬┬┐│┌───┬┬┐│┌──┬┐│
> ││Hi│││││Ho││││hee│││││haw│││││Yo│││
> │└──┴┴┘│└──┴┘│└───┴┴┘│└───┴┴┘│└──┴┘│
> └──────┴─────┴───────┴───────┴─────┘
>
> ; (# # {. )each a: (-.@= <;.1 ]
> )'Hi';'';'';'Ho';'';'hee';'';'';'haw';'';'';'Yo';''
> ┌──┬──┬──┬──┬──┬───┬───┬───┬───┬───┬───┬──┬──┐
> │Hi│Hi│Hi│Ho│Ho│hee│hee│hee│haw│haw│haw│Yo│Yo│
> └──┴──┴──┴──┴──┴───┴───┴───┴───┴───┴───┴──┴──┘
>
> its a bit more complicated with possible leading blank: (this still works
> without leading blank)
>
> ; (# # {. ) each a: (] <;.1~ 1 (0}) -.@=
> )'';'Hi';'';'';'Ho';'';'hee';'';'';'haw';'';'';'Yo';''
> ┌┬──┬──┬──┬──┬──┬───┬───┬───┬───┬───┬───┬──┬──┐
> ││Hi│Hi│Hi│Ho│Ho│hee│hee│hee│haw│haw│haw│Yo│Yo│
> └┴──┴──┴──┴──┴──┴───┴───┴───┴───┴───┴───┴──┴──┘
>
>
>
>
> ----- Original Message -----
> From: Devon McCormick <[email protected]>
> To: J-programming forum <[email protected]>
> Cc:
> Sent: Monday, January 5, 2015 11:06 AM
> Subject: [Jprogramming] Forward fill w/o looping
>
> I just threw together a short J solution that does what I want but it uses
> a loop and a conditional. I'm thinking there's got to be some kind of
> loopless prefix sort of solution but am at a loss to come up with it.
>
> My code looks like this:
>
> fillEmptyFwd=: 3 : 0
> for_ix. i.<:#y do.
> if. 0=#>y{~>:ix do. y=. (ix{y) (>:ix)}y end.
> end.
> y
> )
>
> An example usage would be this:
>
> fillEmptyFwd '';'Hi';'';'';'Ho';'';'hee';'';'';'haw';'';'';'Yo';''
> ++--+--+--+--+--+---+---+---+---+---+---+--+--+
> ||Hi|Hi|Hi|Ho|Ho|hee|hee|hee|haw|haw|haw|Yo|Yo|
> ++--+--+--+--+--+---+---+---+---+---+---+--+--+
>
> Any ideas on something less loopy/conditional?
>
> --
> Devon McCormick, CFA
> ----------------------------------------------------------------------
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>
> ----------------------------------------------------------------------
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> ----------------------------------------------------------------------
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>
--
Devon McCormick, CFA
----------------------------------------------------------------------
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