Alternative (slightly more compact) implementation of tv:
tv=: (0 = {.) *./@, (0 < {:), 1 >: +/\inv
Meanwhile, this is probably a bit long (almost 100 characters) to be
called a one line implementation, but it seems to be in the right
ballpark:
;"1(' - ',&.>' o+|'){~(+3*_1 1&E.)"1&.|:(*
>./\.@:*)0,~2:`(}.@((i:,.]-1:) ~.))`((1,~]#_1:)"0)}~d
-o
|-o
| |-o
| +-o
|-o
+-o
|-o
+-o
+-o
I hope this helps,
--
Raul
On Fri, Aug 7, 2020 at 9:19 AM ethiejiesa via Programming
<[email protected]> wrote:
>
> Do you know a slick way of pretty-printing a tree given its depth vector
> representation?
>
> A vector represents a tree if and only if it satisfies the following:
>
> NB. Tree valid? First node is root node (depth 0), only one root node,
> NB. and all nodes are exactly one deeper than their parent
> tv=: 0&=@{. *. *./@(>&0)@}. *. 1 *./@:>: +/\^:_1
>
> The goal is to produce a nice visualization given a valid depth vector. For
> example, given (d=: 0 1 2 2 1 1 2 2 3), something like this would be ideal:
>
> o
> |-o
> | |-o
> | +-o
> |-o
> +-o
> |-o
> +-o
> +-o
>
> About the best I can do in a single line is this:
>
> NB. Tree print
> tp=: (, LF&,)/@({&' |o-')@((3&*@=/ |:@}.@(,/)@(,:"1&|:) 2&*@=/ +. >/)
> ~.)
> tp d
> o
> |-o
> | |-o
> | | |-o
> |-o
> | |-o
> | | |-o
> |-o
> | |-o
> | | |-o
>
> Trimming the branches, however, is giving me a lot of grief. Can you do
> better?
> I am looking for terse one-liners but am open to alternative visualizations.
>
> Producing segments of "trimmed branches" is a nice little sub-problem. It
> corresponds to finding finding "catenaries", i.e. runs of integers capped on
> the left and right by n, where the intervening integers "droop below" n, i.e.
> satisfy (>:n).
>
>
> Looking forward to your ideas!
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