That's one of my favorite J idioms!
A similarly elegant phrase arising from the use of -. is (, '/' -.~ {:)
'/some/path' . This ensures all paths end in a slash, without duplicating
slashes in paths that are already in canonical form. To appreciate its
elegance, write an analogous function on a
I used the fork [-.-. for interesetion. (-. twice again)
Вс, 08 сен 2013, Joey K Tuttle писал(а):
> Another (related, and also using -. (twice!)) expression that I use a
> lot for getting just the digits from a string -
>
>digits=: -.&(a.-.'0123456789')
>
>digits ": 23 45 6
> 23456
>
>
Another (related, and also using -. (twice!)) expression that I use a
lot for getting just the digits from a string -
digits=: -.&(a.-.'0123456789')
digits ": 23 45 6
23456
On 2013/09/08 19:54 , Alex Giannakopoulos wrote:
That 'less' verb is very useful, I'd never had occasion to use i
That 'less' verb is very useful, I'd never had occasion to use it until now!
It could have been a bit more hyped up in the documentation, though, I'd
never even seen it used before! (blush)
On 9 September 2013 03:46, Alex Giannakopoulos wrote:
> Ah, OK, now I got it!
>
> (": 23 45 6) -. ' '
>
>
Ah, OK, now I got it!
(": 23 45 6) -. ' '
23456
It wasn't working because I used the empty string '' instead of the blank
string ' '. Doh!
On 9 September 2013 03:31, bob therriault wrote:
> Well Dan usually comes up with the really insightful answers, but what I
> see happening is that
Also it works inline, e.g.
-.&' ' &. ": 12 3 4 67 09 0 9
but not in a definition, i.e.
ijoin =: ;@cut &. ":
works, but
ijoin =: (-.&'') &. ":
does not.
On 9 September 2013 03:14, Dan Bron wrote:
> Try -.&' ' in place of ;@cut
>
> -Dan
>
> Please excuse typos; composed on a handheld device.
Well Dan usually comes up with the really insightful answers, but what I see
happening is that & is forcing the ' ' as the right argument. When you supply
your right argument it moves to the left side of -. and then the ' ' (empty
spaces) are removed.
Hope this helps, bob
On 2013-09-08, at 7:
Great, thanks very much!
How does that parse, though? I don't follow.
I see a "hook"? of (NOT bond) and , although it's obviously
not a hook since '' is not a verb.
What am I missing?
On 9 September 2013 03:14, Dan Bron wrote:
> Try -.&' ' in place of ;@cut
>
> -Dan
>
> Please excuse typos;
On second thought this would work for single integers into a number, but if you
wanted to stay with a string, Dan's solution is the better way to go.
Cheers, bob
On 2013-09-08, at 7:15 PM, bob therriault wrote:
> Hi Alex,
>
> For base 10 this might work.
>
> t=: 3 4 5 6
> 10 #. t
> 3456
>
Hi - I need to join up a list of integers (presented as a rank-1 array)
into a single number.
At the moment I am using the following,
;@ cut &. ":
which works, but I wonder if there is something better, not using the
supplied 'cut' verb, which seems like overkill.
Any suggestions hints pointers
Hi Alex,
For base 10 this might work.
t=: 3 4 5 6
10 #. t
3456
Cheers, bob
On 2013-09-08, at 7:07 PM, Alex Giannakopoulos wrote:
> Hi - I need to join up a list of integers (presented as a rank-1 array)
> into a single number.
>
> At the moment I am using the following,
>
> ;@ cut &. "
Try -.&' ' in place of ;@cut
-Dan
Please excuse typos; composed on a handheld device.
On Sep 8, 2013, at 10:07 PM, Alex Giannakopoulos
wrote:
> Hi - I need to join up a list of integers (presented as a rank-1 array)
> into a single number.
>
> At the moment I am using the following,
>
> ;@
Hi there,
I am using the PLOT package.
When using the pd commands text, textc and textr, we have ...
Argument is x y text, where x y are coordinates relative to the current window.
with x, y element of [0 .. 1000] or pixels (using x suffix).
This is fine for some situations, but I would like
"Shaw, Ewart" writes:
> [This is a belated follow-up to posts by Bill Harris & Mike Day, Aug 30th &
> 31st]
>
> I think Mike Day's probably right in recommending following up links
> between J, R & BUGS. Note also the recently published (August 2007)
> paperback "Bayesian Computation with R" by
I am trying to change the grid x and y spacing in the plot routine and
am having a problem finding the correct option. Help would be appreciated.
David
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