http://jsoftware.com/help/dictionary/dictf.htm
"The train N g h (a noun followed by two verbs) is equivalent to N"_ g h ." ;) Actually it's a good sign that you noticed that issue. You've a good eye for detail. Also, the part of http://jsoftware.com/help/dictionary/contents.htm under "Dictionary" can be especially worthwhile if you spend some time digesting it. Thanks, -- Raul On Sun, Jun 1, 2014 at 2:27 AM, Jon Hough <[email protected]> wrote: > Looking at J's Wikipedia page: > > http://en.wikipedia.org/wiki/J_(programming_language) > > I am trying to understand the quicksort example, so I am reading right to > left and trying to understand each part as I go. > > quicksort=: (($:@(<#[), (=#[), $:@(>#[)) ({~ ?@#)) ^: (1<#) > The first part , (1<#), is giving me trouble. It seems to be testing if the > length is greater than one, and then if so the rest of the verb is run. > But from my understanding of tacit verbs, the verb (1<#) should look like > this: > > (1&<@:#) > Example: > > (1&<@:#) 5 6 3 2 > > 1 > and > (1&<@:#) 5 > > 0 > But then also: > (1<#) 5 3 1 > > 1 > So it seems these two verbs are equivalent. So essentially, my issue is why > the & is not needed after the 1, which is the left argument of dyadic <? > Regards. > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
