It is valid, but don’t think it is what was intended … The following 2 statements produce the same result: 3j5 3j5
(3) j. (5) 3j5 And these 2 statements produce the same result also. 3j.4 NB. This is a valid complex constant of 3+i*0.4 3j0.4 (3) j. (0.4) 3j0.4 As Raul pointed out, “j.” is a very, but the sequence 9j9 is part of contiguous word formation (makes a complex constant).…/Rob > On 1 Jul 2017, at 7:33 pm, Martin Kreuzer <[email protected]> wrote: > > Looking at the examples, I came across the difference between > > 3 j. 4 NB. spaces > 3j4 > > and > > 3j.4 NB. no spaces > 3j0.4 > > Given that this (rightfully) throws an error > > .2 .3 .4 .5 > |syntax error > | .2 .3 .4 .5 > > while this doesn't > > 0.2 0.3 0.4 0.5 > 0.2 0.3 0.4 0.5 > > why then is the construct 3j.4 valid..? > > -M > > > At 2017-07-01 04:43, you wrote: > >> > As Henry points out, the NuVoc page is quite a bit clearer on this topic. >> >> Sample google search: >> site:jsoftware.com inurl:nuvoc complex >> >> Quite a bit of reading there, if you have the patience for it (be sure >> to mix in plenty of trial and error, though, or it's a total snoozer). >> >> Thanks, >> >> -- >> Raul >> >> >> On Fri, Jun 30, 2017 at 11:30 PM, Rob Hodgkinson <[email protected]> wrote: >> > Hi Lawrence, the âill-formed numberâ is because "j." is a verb, quite >> > different to âjâ which is part of a noun construct (like 3j4, or 1e3 >> > for 1000). >> >> > So in your examples ... >> >> > NB. But wait, not so fast: >> > 1j.(2^0.5)%2 >> > |ill-formed number >> > NB. No >> >> > NB. Now try to separate the âj.â verb with a space either side to make >> > it clear to J that this is not â1jxxxâ where J would assume you are >> > trying to make a complex constant. >> > 1 j. (2^0.5)%2 >> > 1j0.707107 >> >> > The reason is that J can also directly interpret âcomplex constantsâ >> > entered directly using the j notation (as a continuous sequence of >> > non-blank chars)⦠>> > 3j4 NB. This is a single complex constant 3+i4 >> > 3j4 >> >> > 3 j4 NB. But now J tries to view this as a list of (3) and (j4) >> > which which J would assume is (3) and a variable called (j4). >> > |syntax error >> > | 3 j4 >> >> > As Henry points out, the NuVoc page is quite a bit clearer on this topic. >> >> > HTH, Regards Rob >> >> >> >> On 1 Jul 2017, at 1:14 pm, Lawrence Wickert <[email protected]> >> >> wrote: >> >> >> >> Hello, I am a old EE still trying to learn. I am a real beginner having >> >> no end of problems with specifying complex numbers. I am using j64-804 >> >> on ubuntu 12.04. I am either doing something really stupid or I need to >> >> update to 806. Updating anything gives me heartburn or worse so I hope >> >> it is just my misunderstanding of basic principles. Although I have a bad >> >> habit of RTFM as a last resort I have tried the Dictionary to no avail. >> >> I appreciate any guidance. >> >> >> >> 0j(2^0.5)%2 >> >> |ill-formed number >> >> >> >> 0j((2^0.5)%2) >> >> |ill-formed number >> >> >> >> j.(2^0.5)%2 >> >> 0j0.707107 >> >> NB. Eureaka, OK, I get it! >> >> >> >> NB. But wait, not so fast: >> >> 1j.(2^0.5)%2 >> >> |ill-formed number >> >> NB. No >> >> >> >> 1j(2^0.5)%2 >> >> |ill-formed number >> >> NB. Still No >> >> >> >> 1+j.(2^0.5)%2 >> >> 1j0.707107 >> >> NB. This works! >> >> >> >> Let's try to do something with it: >> >> k=:(0 1+j.(2^0.5)%2 3 4 0 5) >> >> |length error >> >> | k=:(0 1 +j.(2^0.5)%2 3 4 0 5) >> >> >> >> NB. Maybe parantheses will help: >> >> k=:(0 (1+j.(2^0.5)%2) 3 4 0 5) >> >> |syntax error >> >> | k=:( 0(1+j.(2^0.5)%2)3 4 0 5) >> >> >> >> NB. This one has to work: >> >> k=:(0 1j0.7071 3 4 0 5) >> >> k >> >> 0 1j0.7071 3 4 0 5 >> >> NB. It does but it can't be the only way to do it. >> >> >> >> NB. One last rry: >> >> g=: 1+j.(2^0.5)%2 >> >> g >> >> 1j0.707107 >> >> NB. That's nice. >> >> >> >> k=:(0 g 3 4 0 5) >> >> |syntax error >> >> | k=:( 0 g 3 4 0 5) >> >> NB. This isn't nice. >> >> >> >> Lost in the high desert of New Mexico, Larry Wickert >> >> >> >> ---------------------------------------------------------------------- >> >> 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 > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
