Henry, With further thought, I suppose that what is happening is that the array remains a sparse type and that the indices now reflect the new shape after the selection. Which does make sense when I think about it, but I guess I had it in my mind that the indices would remain attached to the values and not be recalculated. At least this is the way that I view this at the moment and look forward to being corrected if I am mistaken.
Cheers, bob > On Dec 20, 2017, at 3:22 PM, robert therriault <[email protected]> wrote: > > Henry, > > I think Brian may be referring to the indices shown in the sparse > representation. > > t=: $. 0 0 1 0 2.5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 999 _ 0 0 0 > t NB. Index values as expected > 2 │ 1 > 4 │ 2.5 > 19 │ 2 > 21 │ 999 > 22 │ _ > _5{. t NB. I would have expected 21 and 22 to match the values in the > original > 0 │ 999 > 1 │ _ > 5 {. t > 2 │ 1 > 4 │ 2.5 > 19 { t > 2 > 5 {. 20}.t NB. It looks like it is reindexing after dropping the first 20 > values > 1 │ 999 > 2 │ _ > > Cheers, bob > >> On Dec 20, 2017, at 3:06 PM, Henry Rich <[email protected]> wrote: >> >> No, _5 {. z has shape 5. >> >> Henry Rich >> >> On 12/20/2017 6:04 PM, Brian Schott wrote: >>> Negative take seems screwy. >>> >>> $ y=: 0 0 1 0 2.5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 999 _ 0 0 0 >>> 26 >>> _5{. z NB. Should the 0 and 1 be large numbers? >>> 0 │ 999 >>> 1 │ _ >>> 5{. z >>> 2 │ 1 >>> 4 │ 2.5 >>> >>> >>> -- >>> ---------------------------------------------------------------------- >>> For information about J forums see http://www.jsoftware.com/forums.htm >> >> >> --- >> This email has been checked for viruses by AVG. >> http://www.avg.com >> >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
