Terrence, Glad to see you haven't given up. In the expression,
> myverb =: dyad : '2 * x >. y'"0 the "0 can be read as 'rank 0'. The double-quote mark is a primitive conjunction known as `rank'. Its left argument is that explicit verb and its right argument is the zero. Bear in mind that in J, any graphic (a member of the printable subset of ASCII which is neither a letter nor a digit) is a primitive. So " is a primitive. You can look up any primitive in the Vocabulary (as you've been doing). A quick way is to position your typing cursor (caret) over the " and press the key combination CTRL+F1. But, since " is such an fundamental and brilliant idea, the Vocabulary page for it may not be the best place to start. Were I you, I'd read Henry Rich's J for C Programmers. The chapter specific to rank is 6: Loopless code I: Verbs Have Rank, and can be found here: http://www.jsoftware.com/help/jforc/loopless_code_i_verbs_have_r.htm#_Toc141157983 -Dan PS: Just in case it's not clear: in J, the double-quote is NOT part of a pair. Just as [ and ] and { and } can each stand alone, so can " . Unlike ' or ( and ) which, unpaired, are syntax errors. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
