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Original post by Sandman Quote: Original post by LucidIon Interesting thread. If you're bothered about stellar drift/jitter you simply allocate the names based on a specific time (such as 00:00:00 1st Jan 1970 UTC ;) Has anyone looked at how Elite worked? It had automagically generated galaxies - with convincing names. Elite does indicate one danger of generated galaxies: planets with names such as Arse - which slipped though Q&A. I don't know about the original Elite, but certainly in Frontier they used actual star names for reasonably notable/nearby stars, and the rest were generated randomly by combining sets of syllables. This produced some fairly unpronounceable names, as well as the odd duplication, it wouldn't surprise me all that much if some slightly silly names got in by chance too.

Yes, I looked at Elite's random name generator. Other than the fact that its names may be duplicated (there's nothing to stop that from happening, esp. since the length of the words are limited, and space isn't), it generates names based on letter adjacency tables.

The thing with letter adjacency tables is that they can occasionaly produce unpronouncable names. I feel confidant in my system, that all names produced are pronouncable (except for the rare grouping of two identical th, ch, or sh's, such as raththal)

I do like the idea of deciding their positions for naming based on a specific period in time. Although 1970 is abit arbitrary (galactically speaking. I don't think hundreds of years from now anyone will care about how our computers tell time [wink]). But I have no suggestions for a better time point. I suppose anytime would do.

[Edited by - Numsgil on August 24, 2004 2:33:09 PM]

I hate to be stupid, but why PERMUTATIONS instead of COMBINATIONS?

I don't believe that the coordinate system cares about the order in which the stars are located, for the first 6 that is. Obviously the last coordinate (the origin point) has to be entered last.

Anyway, I look forward to being enlightened...

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Original post by NexusEnt I hate to be stupid, but why PERMUTATIONS instead of COMBINATIONS? I don't believe that the coordinate system cares about the order in which the stars are located, for the first 6 that is. Obviously the last coordinate (the origin point) has to be entered last. Anyway, I look forward to being enlightened...

Although I'm sure it is possible to create a co-ordinate system based on combinations, I wouldn't want to be the one to do it.

Examine the simple case of the cartesian system. Points are represented as (x,y), where order is important. That is, (1,0) is not the same as (0,1).

The same holds true for all other common coordinate systems I've ever seen. In fact, I've never seen a coordinate system based on combinations.

So, we use permutations instead of combinations because order is important to the representation.

I understand that, but this coordinate system is using the intersection of the lines drawn between the first 6 coordinates, to find the middle, then drawing a line to the origin.

So that is what leads me to say that the first 6 are not permutations but a combination.

Just somantics for me really, but it would be good to know.

Ummmmmm, why not simply use polar coordinates for the starts with the galacitc center being the origin? (of course)

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Original post by SteevR Ummmmmm, why not simply use polar coordinates for the starts with the galacitc center being the origin? (of course)

I assume you're asking why not use spherical coordinates. Polar are based on 2-D. Spherical are 3D. Cylindrical are polar coordinates with a z element tagged onto the end.

Spherical would be ideal if you were using a roughly spherical area, say a galactic cluster or a smaller subsection of a galaxy. However, our galaxy is roughly flat, (visible stars anyway. I'm not sure how the halo affects the shape), so IMO cylindrical would be the way to go to name stars.

But a spherical would work fine too. It would just mean that you'd need two syllables for each angle, and two for radius, which means you'd need 6 syllables just for the position data.

Compare that with two syllables for angle and distance, and one syllable for distance from the galactic plane. You get 5 syllables for positional data. Obviously superior.

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I understand that, but this coordinate system is using the intersection of the lines drawn between the first 6 coordinates, to find the middle, then drawing a line to the origin.

I assume you mean the order of the syllables when making up the end name. In this case, the only way for the name to make sense is to realize that the first two syllables corresponds to x, the next two to y, etc. This is where the permutation nature comes from. You can be arbitrary with the placement of the meanings of various elements, so long as you're consistant.

Now, if you assign each syllable to be only applicable in one area, this changes. For example, suppose 'Ra' is only used in context of radius from the core. Now you can use combination math. Each syllable's order no longer is needed to understand the encoding.

There might be some times when you want to use a name based on combinations instead of permutations, but they must be fairly rare, or else all major coordinate systems would be based on combinations instead of permutations, right?

Well if you are trying to place a syllabic correllation then I agree you would have to use permutations.

But otherwise I say its only a combinatorial coordinate system since it doesnt matter the order in which the first 6 are chosen because the middle/intersection of those 6 is the same.

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Original post by Numsgil Quote: I understand that, but this coordinate system is using the intersection of the lines drawn between the first 6 coordinates, to find the middle, then drawing a line to the origin. I assume you mean the order of the syllables when making up the end name. In this case, the only way for the name to make sense is to realize that the first two syllables corresponds to x, the next two to y, etc. This is where the permutation nature comes from. You can be arbitrary with the placement of the meanings of various elements, so long as you're consistant.

Nah.. He's talking about the chevrons from Stargate. 6 points to define 3 crossing lines and another for the orign..

To answer his question:
The reason they're using permutations instead of combinations is that it doesn't make sense to use a chevron more than one time (which would be possible in a combination). The 6 first chevrons gives the coordinates for the 6 points. Since you need lines between the points you can't use one point more than one time. Check out this page.

I know the difference between permutations and combinations, and the combination formula is already not allowing for duplicates...thats simply a part of it.

And yes I am trying to state, and willing to be corrected, that it is not permutations because the all you need is the intersection of the lines connecting the first six points to find the destination, and then the seventh to form the origin.

I was trying to see if this coordinate system had a name...anybody know?

Bump....sorry..