postcode to coords automation

[timd]

Quote: Originally posted by desgb on 14 June 2003

---

And how are your co-ordinates determined? Do you intend that when navigating to a postcode, the centre of the postcode is what is navigated to? How big are postcode areas.... do they differ, and if so, what is the largest postcode area?

---

I'm sure I read somewhere, though I can't find it now, that the co-ordinates for a postcode represent the start of a postman's "walk". A full postcode might represent a single floor of a building, or it might represent a number of houses, so the size does vary. I would have thought that the postcode would be enough to get you within a few hundred metres in most cases. It might be worse in more remote areas, anyone know for sure?



I think that the primary benefit of this would be to find streets that are badly organised in the Tom Tom database. eg on a recent trip to Minehead, I had trouble finding any streets there, as Minehead is not listed in the database. Minehead's streets were all listed under something like West Somerset. If you can't even find the city/town, it is pretty hard to find the streets! A postcode lookup would have been helpful in this situation and even if it was slightly out, making a small manual adjustment would be no hardship.



Incidentally, I've just had a look at the NHS postcode directory that I have access to here at work, and you might be interested to know that there are 1.7 million current postcodes!

[desgb]

zoyah,



Now that I understand what you are doing - you are to be congratulated! fysmd has a good point though, as TomTom seems to take a long time when searching for street names; but does this really apply with a POI file?



And how are your co-ordinates determined? Do you intend that when navigating to a postcode, the centre of the postcode is what is navigated to? How big are postcode areas.... do they differ, and if so, what is the largest postcode area? If it's really large, TomTom might navigate to the centre of the postcode but you could still end up some distance from where you want to be.



And why haven't TomTom done what you are working on - might there be other pitfalls? I'm definitely interested in being able to navigate to postcodes though, so good luck, and keep up the great work. Speaking of which - can you use any help in what you are doing? If not very time consuming, I'm sure lots of people using this forum would be glad to help (as long as you would be able to verify any work they might do). How does your script work?



Regards,



Des
_________________
greggery peccary... the gregarious wild swine

[fysmd]

Excellent!!



It hadn't actually occurred to me that a POI file with ALL postcode data could be produced..

AFAIC a stripped postcode file as you describe would be fine (how long does it take to search for an entry in such a large POI file!?).



I was interested in using a script which I could feed post codes into so I could produce POIs for hotel chains, McDonalds, BK etc..

[zoyah]

The script is working, I have 40000 UK postcodes so far. Am focusing on the Greater London area (and then plan to go to Surrey). Any suggestions on Counties/Regions to prioritise after that?



here is a sample of the ASCII file:



-0.117932,51.539425,"N1 0AA Greater London, Islington, Barnsbury, Canonbury"

-0.118833,51.539611,"N1 0AB Greater London, Islington, Barnsbury, Canonbury"

-0.120592,51.538551,"N1 0AD Greater London, Islington, Barnsbury, Canonbury"

-0.122367,51.537482,"N1 0AE Greater London, Islington, Barnsbury, Canonbury"

-0.116822,51.537654,"N1 0AF Greater London, Islington, Barnsbury, Canonbury"

-0.121090,51.539080,"N1 0AG Greater London, Islington, Barnsbury, Canonbury"

-0.121928,51.537268,"N1 0AH Greater London, Islington, Barnsbury, Canonbury"

-0.122367,51.537482,"N1 0AJ Greater London, Islington, Barnsbury, Canonbury"

-0.122147,51.538971,"N1 0AL Greater London, Islington, Barnsbury, Canonbury"



Am concerned about the file size, it is going to be HUGE when I'm done. Anyone know what the POI limits are in TTN2? Managed to get it to work with 16000 entries no problem.



To cut down file size, am thinking of remonving all data after the postcode and the space between the outcode and the incode, so it will look lomething like this:



-0.122147,51.538971,N10AL



Would this be good enough? Any other suggestions or comments?

[fysmd]

I'm interested in a script which will take the complete postcode as input and output co-ords.

Really neat if the results could keep a comment field:

Input:

po12 3cd,A sample POI



Output:

x.xxxxx, y.yyyy, A sample POI



or similar, this way the comment stays intact.

[desgb]

zoyah,



If this can be made to work with OS Landranger references and Streetmap conversion to a .asc or .txt file which I could then convert to a .ov2 POI file, I'd be very interested. Currently I have to input Landranger references into Streetmap, copy & paste the Latitude/Longitude results, edit out the text I don't need (difficult to copy properly from a table), reverse the info to Longitude/Latitude, and enter my comment for what the POI represents.



VERY laborious - if I could just enter my Landranger reference and a comment, then the rest be automated that would be fantastic, a huge timesaver.



Thanks and Regards,



Des
_________________
greggery peccary... the gregarious wild swine

[zoyah]

I have a list of outcodes (first part of the postcode) and have a script that queries Streetmap. Now all that remains is for me to write the loos that will go through all the incodes. Anyone interested?

[zoyah]

Have you managed to get a list of the postcodes? I have previously played with the Streetmap link gstenson mentioned and it would be very easy to put a script together that will read in the postcodes from a .csv file and then extract the all the relevant info (postcode, lat and long) to anotehr file to be converted to a POI file.

[fysmd]

Anybody know of a fast (& free) way of translating postcode to co-ords? I use streetmap which is great but VERY time consuming, is there a site which takes a number of postcodes at once, or is automatable?

[zoyah]

FYI



Have also submitted the following POIs to Dave:



Postcode Search - Central London (2 mile radius)

Postcode Search - Central London (5 mile radius)

Postcode Search - Surrey



The search is much quicker in these files. The first 2 are subsets of the Postcode Search of Greater London that I mentioned in my previous post.

[jmaddock2]

All

I have converted the full 1.7 Million Postcodes for the UK and made it available at the following URL

http://www.ansas.co.uk/postcode/poi.htm

Files are split into 6 easy to search POI files (34 MB total)

If you would like the files on CD please email me on

jmaddock@ansas.co.uk

Enjoy

[Oldie]

[Heyou]

Well lets hope that between you boffins you can sort this out, it's a feature that TT2 is crying out for. I d/l'd all of Oldies Codesearch's and then copied them into the maps directory 225 files in total (no problem with numbers of files). But when i started TT2 it gave an error "too many POI's" it still started but not all POI are listed - 118 were listed i think.

I still have to put on the Speed Camera and several other POI's so this is a non starter if the limit is approx 100 POI's.

I'm making an assumption here but does TT2 and all others work at a base level of Co-ordinates positioning, of course no one knows these off by heart so they ask for a Town and Street and if it exists then it gets the co-ordinates and puts an X on the map.

These post code to co-ordinate converter progs that are around - surely just take the entered postcode, do the search for this entry in it's database and returns the co-ordinate entry if found. Assuming this database of postcode matched upto Co-ordinates are available, it can't be beyond the wit of man to write an app that intervenes when you select "Go to Co-ordinates" in TT2 this then prompts you for a postcode returns the co-cordinte and then fills in the Co-ordinates field, just leaving you the task of pressing OK to see it on the map.

Of course i say all this crap not having a clue how to do this myself but it must be possible, GPSAssist grabs input meant for TT2 does it's thing with it and passes it back to TT2 to finish the job.

Power to you all, good luck and give us a shout when you've cracked it :o)

Del.
_________________
Good judgement comes from experience. Experience comes from bad judgement

[Oldie]

[Heyou]

Richard, first off let say the codesearch POI are great, i loaded up the south east, west & central and it's excellent. Of course i then made a pig of myself and tried to load up the whole country, which is where TTN2 then failed. I haven't tried Codesearch, where do i find it?

I'm a bit long in the tooth now to start learning a language to get this job done, a few years ago i would have pulled my sleeves up, got the manual out and written something. It's all i can do these days to get the video recorder to record the right programme ;o)

I seem to be having more and more senior moments these days.

Del.
_________________
Good judgement comes from experience. Experience comes from bad judgement

We see you’re using an ad-blocker. We’re fine with that and won’t stop you visiting the site.
Have you considered making a donation towards website running costs?.
Or you could disable your ad-blocker for this site. We think you’ll find our adverts are not overbearing!