Talk:Box the compass

General

The naming sequence was more complex than I originally thought. I started by coding up a generic quarter of the points but North and South take precedence over East and West in some of the orderings and so I had to 'reflect' a quarter, quarter1 to make quarter2 in the Python solution.

P.S. Couldn't help the Pirate speak :-)

--Paddy3118 21:43, 27 March 2011 (UTC)

I chose to just put in a list of all the packed representations (which are very slightly modified from the official abbreviations to add hyphens). The fact that I don't have to do a lot of quoting of the strings makes this a very attractive option in Tcl. –Donal Fellows 10:10, 28 March 2011 (UTC)

I like the way you've done it. Coding all 32 points is done so compactly and you skip all the logic for choosing quarters. Neat! --Paddy3118 12:53, 28 March 2011 (UTC)

In my VB.net implementation I chose to build the list of points into an array beforehand and keep it separate from the calculation subroutine. It was implemented in a similar way to the Python routine otherwise. Admittedly, it'd probably have been more efficient just to write the list of points straight into the array, but would have been far less interesting that way! --TheMadman 13:31, 28 March 2011 (UTC)

For J, I decided to do the simple thing, and then I fix the result by preventing the text of the first word from appearing multiple times in multi-word names. --Rdm 15:35, 28 March 2011 (UTC)

The walk through the table (the actual degrees used) struck me as odd. Basically a sawtooth walk going from lowest to middle to highest as each row is advanced. When I saw the task I expected to see the midpoints as the most obvious. Not sure what the reason was and it's not really important if your function translates an angle to a compass point. I suppose it test finding the edges. Was there a specific reason for that pattern of angles? --Dgamey 15:39, 23 April 2011 (UTC)

Hi Dgamey, yes it was to test the ranges corresponding to a particular point of the compass but still be easy enough to check. --Paddy3118 18:51, 23 April 2011 (UTC)

Capitalization?

The Wikipedia article capitalizes, for example, "Southwest by south". However, a google search shows that as a general rule the capitalization will be either "southwest by south" or "Southwest by South". The Wikipedia capitalization could be rationalized as the lower case variation as it would appear at the beginning of a sentence... Anyways, perhaps the task description should either explicitly require one form of capitalization (and I do not much care which, though the Wikipedia form seems awkward) or should explicitly state that capitalization is a non-issue? --Rdm 14:50, 28 March 2011 (UTC)

The current J implementation abuses the information contained in the wikipedia capitalization to deal with one of the wording quirks. (I would prefer to get rid of that abuse but do not want to code so generally that I am explicitly parameterizing and supporting all three forms of capitalization -- at least not if the task does not require it.) --Rdm 15:10, 28 March 2011 (UTC)

Hi Rdm, What is important is matching the capitalisation of the wp table. But I just looked at the capitalization from the OED, which seems to point to south being lower cased for cardinal points, (except when starting a sentence of course). --Paddy3118 15:39, 28 March 2011 (UTC)

I would argue that the capitalisation is a bit of a non-issue. Strictly speaking, the cardinal directions are not proper nouns therefore shouldn't really be capitalised. I did capitalise mine in the same way as the Wikipedia entry simply because it just wouldn't have looked right otherwise, but I did make sure that the capitalisation subroutine acted on the direction names at display time, not on insertion into the array. --TheMadman 15:32, 28 March 2011 (UTC)

It should appear as in the wp table. Other capitalisations wouldn't be following the task description. --Paddy3118 15:39, 28 March 2011 (UTC)

Absolutely, although if you look at the example at the bottom of the page, the Wikipedia entry does put "east by north" in lower case, suggesting that it's done in the table purely for aesthetics (which, in those circumstances, is probably the correct way to write it), hence my argument of non-issue. --TheMadman 15:50, 28 March 2011 (UTC)

I would also argue that capitalization should not be an issue. If you get concerned about something like that, you're starting to worry about the brand of mustard on the hamburger instead of the actual meat. --Mwn3d 16:11, 28 March 2011 (UTC)

J and task specifics

What should I do about the J solution. No doubt, as the comment seems to suggest, J makes sure that the compass point for all three angles in its fuller row of three headings are all the same, but I am concerned that:

1. Others will just look at J's solution and not check.
2. It is not strictly comparable to other entries.
3. The full wp table misses out -5.62 and 365.62

For these reasons, I am inclined to stick an incomplete tag on the J example and require it to produce what was asked for; or add to their current entry another version that does strictly what was asked for. Would this be OK Rdm? --Paddy3118 15:54, 28 March 2011 (UTC)

I think I understand your concerns, ... (Editted: and the task description now matches them). --Rdm

Hi Rdm, the task has the note on computing the index and headings to convert that isn't in your current example but is in others. --Paddy3118 19:48, 28 March 2011 (UTC)

I believe I have the compass index in the J implementation. I believe I have included all the headings asked for in the task description. I believe the headings I use are in the same order that they are specified in the task description. So I am not sure what you meant here. Is it possible you were looking at a cached version of the page when you wrote this? --Rdm 20:26, 28 March 2011 (UTC)

Hi Rdm, points at index 7,15,23,31 are off slightly. (The wording of the point). --Paddy3118 20:01, 28 March 2011 (UTC)

Thank you, fixed. (I now sort the hyphenated words so that the shortest name in the pair comes first.) --Rdm 20:19, 28 March 2011 (UTC)

ALGOL's Traditional wind points

I tracked them down to being the names of Mediterannean winds. Nice to know. (here is one of many references or track each name in wikipedia individually). --Paddy3118 06:11, 16 June 2011 (UTC)

Task clarification needed

I think the interval between two neighboring directions is exactly 360/32=11.25 degrees. It is conforming to the Middle column of the table in the wikipedia article. So I do not understand the meaning of the given sequence of numbers: [0.0, 16.87, 16.88, 33.75, 50.62, 50.63, 67.5, 84.37, 84.38, 101.25, 118.12, 118.13, 135.0, 151.87, 151.88, 168.75, 185.62, 185.63, 202.5, 219.37, 219.38, 236.25, 253.12, 253.13, 270.0, 286.87, 286.88, 303.75, 320.62, 320.63, 337.5, 354.37, 354.38]. Sorry for my english:) Insolor 12:09, 24 June 2011 (UTC)

I think those numbers are to demonstrate that the ranges are properly positioned and sized. The middle of the ranges may be 11.25 degrees apart, but the different directions that a compass can show (in degrees) are not. It just so happens that we name 16.88 degrees "North-northeast" because it's closest to that named direction (centered at 22.5 degrees). --Mwn3d 12:58, 24 June 2011 (UTC)

Understood, they are to test the function. Thanks. Insolor 16:25, 24 June 2011 (UTC)

Odd omission from task description

In 1. the task requires you to write a function that translates degrees to points, and then in point 2. doesn't in fact require you to test that function. Many of the solutions cheat and just use the index of the test entries (0..32) rather than the actual angles to construct the point-name table, so the scattering of the acceptance values is, in fact, completely useless. Printing out the angle makes it appear that the angle to point translation is being tested, when in fact it isn't. I was going to mark the Perl entry as incorrect, when I realized that it was fulfilling the letter of the task without fulfilling the spirit. --TimToady 17:50, 16 July 2011 (UTC)

Thanks TT. That was the previously unwritten intent of the task. I've updated it and need to add some incorrect tags. --Paddy3118 19:36, 16 July 2011 (UTC)

Why C needs fixing

Hi Ledrug. If you follow this link copied from the task description: box the compass to the wp article it shows the original table. Note that the last index wraps around to 1. There is no 33. If you then check the note part of the task description, the pseudo code incorporates a modulo on the index. I do make mistakes, and I try and learn from them when I make them, but I believe that I legitimally flagged a problem with the C code as presented. --Paddy3118 05:23, 28 November 2011 (UTC)

For one, the indices are just row count, nothing more, becuase there's no legitimate reason to associate numbers to cardinal directions, that's what the names are for. If you want a numeric representation of directions, maybe you should consider using, I don't know, degrees? Secondly, the wp table may justify wrapping table indices around, because its first row centers on 0 while last row centers on 360, which are really the same direction. Numbers here are slightly off center, I don't see why one should give the impression 354.38 is the same as 0 by forcing the last row index to 1 ("just because a table on WP wraps"? Please.) You want to know the direction, read the second column. I don't care what the pseudo code in the task does: translating degrees into direction names should not depend on that. --Ledrug 05:48, 28 November 2011 (UTC)

Except that we are asked to reproduce the table; and the algorithm for both the degrees and the indices is a given part of the task. Not doing the indicated change is to solve a different task.

There still is allowed a fair degree of freedom in interpreting the goals of the task, for example in the ommision of bounding boxes; the order of the three columns; the justification of values in the three columns. Changes to those have not been an issue. Some others have managed to add even more information in their solutions whilst still satisfying the task.

For this task, you are not asked to interpret the validity of the index column of the table, merely to reproduce it, as this should lead to a simpler task of the form "Do this", "Like this". Your insights might well hold technical merit, and might best be added to the wp talk page, but they go beyond the needs of this simpler RC task. --Paddy3118 06:22, 28 November 2011 (UTC)

What is the task? To reproduce the wp table which defines the angle ranges of each direction? Then what are the input numbers for, particularly when they are neither center nor edges of the 32 directions? Or is the task asking to translate those numbers into corresponding direction names, hence the word "reproduce" is a farce anyway? I don't think I had any deep "insight" on this, the task is merely lousily worded if you had some well defined goal in mind. --Ledrug 07:38, 28 November 2011 (UTC)