Sorry, many misprints: Yes, I am reading "J for C" now. But, of course, I understand most of the things described there.
On Sat, Nov 19, 2011 at 12:13 AM, Alexander Epifanov <[email protected]> wrote: > Yes, I am ready J for C now. > But, of course, I understand most if the things. > > The main error: I thought that J is like K, but has more features. > The problem I found: J vocabulary has much more verbs. Most of the > verbs in K is one symbol, in J there are a lot of one-two-three symbol > verbs and many special construction. K is much simpler at the point . > Sometimes it is hard for me to understand what is it: 1 2 +/@:* 3 4 or > 1 2 (+/ @"*) 3 4 or 1 2 (+/@ "*) 3 4. But 5!:2 should help. > > For example I would write the following example in K: > *>|/ > and for me it looks easier at the moment. Will try to overwrite it J. > > Regards, > > On Fri, Nov 18, 2011 at 11:40 PM, Kip Murray <[email protected]> wrote: >> By all means, post questions here. >> >> And I think you will like J for C programmers (click on JfC at top of >> vocabulary page), here is a sample from Chapter 2 Culture Shock: >> >> Here's an example. Figure out what the following code does: >> >> int i, j, maxcol = 0; >> float maxval = x[0][0]; >> for(i = 0;i<=xsize0;++i) { >> for(j = 0;j<=xsize1;++j) { >> if(x[i][j] > maxval) { >> maxval = x[i][j]; >> maxcol = j; >> } >> } >> } >> >> Not too hard. When the code finishes, maxval is the largest element in >> the array x, and maxcol is the column number it was in. As it happens, >> all I wanted was the column number, but there was no way for you to know >> that. >> >> The same code in J: >> >> maxcol =. (i. >./) >./ x >> >> With some practice, you will learn to read this code just as easily as >> you read the C. You will recognize the / as an indicator of a loop that >> accumulates a result, and the i. as an indicator of a search. The =. >> and =: tokens indicate assignment. >> >> What happened to the if statement? >> >> It's built into the >. primitive. Just as most loops are hidden inside >> primitives, so are most conditionals. The functions you write can also >> contain built-in conditionals. >> >> What's the statement delimiter? >> >> There isn't one. Statements are exactly one line long. >> >> I've looked at some J code. Every other character is a period or a >> colon. I've got spots before my eyes. How can anybody read this stuff? >> >> . . . >> >> >> On 11/18/2011 3:45 PM, Raul Miller wrote: >>> If you cannot find the right reference material, then just post questions >>> here. >>> >>> We have a "J for C Programmers" book, but we do not have a "J for K >>> Programmers". And in some ways, J is more complicated to use than K. (K >>> tends to be simpler for 1 dimensional data and for tree structures.) >>> >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm >> > > > > -- > Regards, > Alexander. > -- Regards, Alexander. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
