On Fri, Sep 5, 2008 at 9:31 AM, Markus Schmidt-Gröttrup
<[EMAIL PROTECTED]> wrote:
> How must the results be combined other than with ,/ such that empty path
> results just disappear?
The empty path is being produced by search_paths"_ 1
g=:5 1 2,8 2 3,:7 1 3
search_paths =: 4 : 0
NB. t =: ending vertex not within path and starting vertex equals path end
t=.( -.({:"1 x) e. }.}: y)*.(1{"1 x)={:y
(({. y)<.t#{."1 x) ,.(}. y),"1 0 t#{:"1 x
)
g&search_paths"_ 1&.>^:0 1 2 3 <,:_ 1
+---+-----+-------+-----+
|_ 1|5 1 2|5 1 2 3| |
| |7 1 3| | |
| | |0 0 0 0| |
+---+-----+-------+-----+
You can eliminate them by explicitly discarding them
([: ; [: -.&a: <@(g&search_paths)"_ 1)&.>^:0 1 2 3 <,:_ 1
+---+-----+-------+-----+
|_ 1|5 1 2|5 1 2 3| |
| |7 1 3| | |
+---+-----+-------+-----+
Note also that boxing and razing achieves the same end as ,/
To deal with your termination problem, I think that you
should change your definition for search_paths:
search_paths =: 4 : 0
NB. t =: ending vertex not within path and starting vertex equals path end
t=.( -.({:"1 x) e. }.}: y)*.(1{"1 x)={:y
r=.(({. y)<.t#{."1 x) ,.(}. y),"1 0 t#{:"1 x
if.0=#r do.,:y else.r end.
)
_1 {:: ([: ; [: -.&a: <@(g&search_paths)"_ 1)&.>^:a: <,:_ 1
5 1 2 3
7 1 3 0
--
Raul
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