]x=.1 3 5;2;3 4
┌─────┬─┬───┐
│1 3 5│2│3 4│
└─────┴─┴───┘
{x
┌─────┬─────┐
│1 2 3│1 2 4│
├─────┼─────┤
│3 2 3│3 2 4│
├─────┼─────┤
│5 2 3│5 2 4│
└─────┴─────┘
Wow! I had no idea monadic { could do that to an already-boxed array! Till
now I had always used monadic { just to box vectors, just like <
{1 2 3
┌─────┐
│1 2 3│
└─────┘
<1 2 3
┌─────┐
│1 2 3│
└─────┘
Thanks Henry & Chris.
Where is the doc describing that monadic { feature?
,/> is nice as well, and this I understand. It's just insert/ravel. Turns a
3x2x3 array into a 3x6 array.
Skip Cave
On Sun, Dec 20, 2020 at 12:51 PM Henry Rich <[email protected]> wrote:
> ,/>{x
>
> Henry Rich
>
> On 12/20/2020 1:48 PM, Skip Cave wrote:
> > I have three lists stored in x:
> >
> > ]x=.1 3 5;2;3 4
> >
> > ┌─────┬─┬───┐
> >
> > │1 3 5│2│3 4│
> >
> > └─────┴─┴───┘
> >
> > I want to find all possible combinations of the elements of these lists
> > (taking one from each list).
> >
> > Using the odometer function I can generate all the possible index
> > combinations of selections from those three lists:
> >
> >
> > odo ;# each x
> >
> > 0 0 0
> >
> > 0 0 1
> >
> > 1 0 0
> >
> > 1 0 1
> >
> > 2 0 0
> >
> > 2 0 1
> >
> >
> > Now I can individually find each selection from the three lists
> >
> >
> > ;0 0 0{ea { >x
> >
> > 1 2 3
> >
> > ;0 0 1{ea { >x
> >
> > 1 2 4
> >
> > ;1 0 0{ea { >x
> >
> > 3 2 3
> >
> > ;1 0 1{ea { >x
> >
> > 3 2 4
> >
> > ;2 0 0{ea { >x
> >
> > 5 2 3
> >
> > ;2 0 1{ea { >x
> >
> > 5 2 4
> >
> >
> > How can I generate all of the selections in one 6x3 matrix using just one
> > statement, with no explicit looping?
> >
> >
> > Skip
> >
> > Skip Cave
> > ----------------------------------------------------------------------
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>
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