National Postcodes to be introduced

recedite

mackerski wrote: »

A co-ordinate system (which is what Loc8 is) will not give us a postcode. Specifically, without a central database of each address in the country, any given property could be addressed by a great many co-ordinates, given that houses and land parcels have extent and are not simple points.
So which of the many possible co-ordinates should be the actual postcode to be used as the unique reference for your address? The government has chosen to build a database to solve this problem. This effort is extensive and therefore expensive, regardless of the implementation details of whatever code you chose to use.
The encoding isn't the expensive bit, basically.

The front driveway/avenue should do for country houses, this would allow emergency services and couriers to drive straight in from the road. In the case of hotels, they might like to give out 2 or more codes; one for the main car park out the back, and one for reception at the front.
I don't see this as a problem, I see it as an advantage. It's user controlled and self-maintaining.
Also, there is no problem generating a code for a new building site, or a forest car park, a nice beach or an old castle.

If the govt. require a database for collecting taxes, they should use the MPRN database, which is also used in all BER energy rating registrations; the floor area of houses is also recorded there. There are even a couple of houses "off grid" (without mains electricity) that have been assigned virtual MPRN numbers already.

In a block of apartments, for example, the location code would be the same for everyone in the block. The postman also delivers to one point in the hallway, using the digital sort code that An Post have been using for years.
But each apartment has its own separate electricity meter and MPRN number. This is how the govt. could keep track of them, without the extra cost to the taxpayer of setting up yet another property database.

SpaceTime wrote: »

Hmmm My MPRN locates the wrong address lol

Very common because the builder often wants a connection and submits a rough address before the house/ estate is finished and officially named. All you do is contact ESB networks and have it updated.

Delphic

BailMeOut wrote: »

don't ESB and Bord gas 'own' these systems? What if they decide they want huge payments from the post office or courier companies to use these numbers. System has to be open and freely usable and not at the behest of any other 3rd party.

AFAIK, geo-locations for GPRN and MPRN both have used GeoDirectory to add geo-coordinates to their databases. They can't re-use them without appropriate licence/payment to them.

Curly Judge

BailMeOut wrote: »

very different situation. I am talking about not wanting a private 3rd party entity own the keys and intellectual rights to how every business and home is addressed and ultimately how all goods are picked up and delivered.

I don't see why not.
The Dept of Communications will still be in overall charge and no doubt will appoint a regulator of some kind just as they do with the private companies that provide us with our telephone services.
They can pull the plug at any time if the location code provider is found to be in breach of care or contract.
You have no problem with an English company coming in to run this service but you are afraid to give an Irishman a break?

BailMeOut wrote: »

This is going to the best €25m ever spent

That phrase has a familiar ring to it...... Oh yes....I remember now....
"The irish Bank guarantee will be the cheapest bailout in history."

sigmundv

Just assign a number to each postal district. How difficult can it be? This works in Scandinavia, so why not in Ireland. See for example the Norwegian system, which is described briefly here: http://en.wikipedia.org/wiki/Postal_codes_in_Norway

Norway is also divided up in counties, and there is a range of numbers for each county, as you can see in the above mentioned article. The lowest numbers are for Oslo, the capital, then they increase with distance from Oslo. I system like this should be fairly straighforward to implement.

PS: I just saw an article in the Irish Times describing this, and the plan is that each house has it's own alphanumeric code. Of course that's much more elaborate than what I outlined above.

Delphic

Curly Judge wrote: »

I don't see why not.
The Dept of Communications will still be in overall charge and no doubt will appoint a regulator of some kind just as they do with the private companies that provide us with our telephone services.
They can pull the plug at any time if the location code provider is found to be in breach of care or contract.
You have no problem with an English company coming in to run this service but you are afraid to give an Irishman a break?

Any Irishman? Or any Irish company? There'll be plenty of Irish men and women and Irish companies involved in this project over the next 18 months. Stands to reason.

SpaceTime

Because we are not implementing a simple postal sorting aid which is what most European post codes are.

What would be the point of it? The problem in Ireland is an inability to find individual houses.

the proposed system gives each building a unique identifier in a country with very vague and confusing addresses and many non unique addresses.

It's a good solution to an Irish problem and it has been debated over and over on this thread for years.

I think the conclusions reached on this thread are fairly similar to the conclusions reached by the department even if the minutia of how it works might be argued about, theres a consensus that it absolutely needs to be a level of granularity that can identify a single building.

The system used in Scandinavia isn't aimed at doing what this coding system will do.

The old numeric postcode systems used in most countries only really were there to make it possible for old automatic letter sorters to read the final line of addresses to send an item to the correct local area. They are useless for GPS.

What's being proposed here is a world first.

Delphic

SpaceTime wrote: »

Because we are not implementing a simple postal sorting aid which is what most European post codes are.

The proposed system gives each building a unique identifier in a country with very vague and confusing addresses and many non unique addresses.

I think the conclusions reached on this thread are fairly similar to the conclusions reached by the department even if the minutia of how it works might be argued about, theres a consensus that it absolutely needs to be a level of granularity that can identify a single building.....

What's being proposed here is a world first.

Agreed. The implementation of it is the time-consuming piece, but worthwhile doing well, so that it gets adopted relatively quickly as opposed to postcode systems that took years in some other countries. E-retailing will be a big driver of this, along with access to public, social and financial services eventually. Logistics and delivery companies will certainly welcome it given that it will go to letter box level, and allow them to work out/optimise their own routes/systems.

sigmundv

SpaceTime wrote: »

The old numeric postcode systems used in most countries only really were there to make it possible for old automatic letter sorters to read the final line of addresses to send an item to the correct local area. They are useless for GPS.

What's being proposed here is a world first.

I realised that after I had finished writing my post, which rendered it kind of obsolete. Anyway, good luck with designing and implementing a good system. And please don't privatise it.

BailMeOut

Curly Judge wrote: »

I don't see why not.
The Dept of Communications will still be in overall charge and no doubt will appoint a regulator of some kind just as they do with the private companies that provide us with our telephone services.
They can pull the plug at any time if the location code provider is found to be in breach of care or contract.
You have no problem with an English company coming in to run this service but you are afraid to give an Irishman a break?



That phrase has a familiar ring to it...... Oh yes....I remember now....
"The irish Bank guarantee will be the cheapest bailout in history."

not sure I am making my point very well. The code pin pointing to a house will use some mathematical intelligence, concept or algorithm. This piece of technology and intelligence needs to be ours. Should we use some private solution under license we potentially end up at the mercy of this company forever. That's all I am saying. Who runs and administers it I do not care. If it is ours then there is no reason the state cannot license usage of the pin pointing system to shipping and delivery companies meaning that it can even generate revenue for the state.

All I know is that it is 2013 and I cannot order anything online as DHL, UPS, Fedex, etc... cannot ever find my house and I dread the day if I ever have to call 999. The only deliveries I can ever get are via my postman. I also do some business in the states and good luck dealing with shipping people over there trying to courier you something and they tell you they cannot print a shipping label as there is no post code.

Curly Judge

BailMeOut wrote: »

not sure I am making my point very well. The code pin pointing to a house will use some mathematical intelligence, concept or algorithm. This piece of technology and intelligence needs to be ours. Should we use some private solution under license we potentially end up at the mercy of this company forever. That's all I am saying. Who runs and administers it I do not care. If it is ours then there is no reason the state cannot license usage of the pin pointing system to shipping and delivery companies meaning that it can even generate revenue for the state.

All I know is that it is 2013 and I cannot order anything online as DHL, UPS, Fedex, etc... cannot ever find my house and I dread the day if I ever have to call 999. The only deliveries I can ever get are via my postman. I also do some business in the states and good luck dealing with shipping people over there trying to courier you something and they tell you they cannot print a shipping label as there is no post code.

Thanks!
Mostly I agree with your analysis and the proposed system is surely an improvement on the previous postal code dinosaur.
But....are you in all seriousness suggesting that gallant little Ireland is going to go out and, on the well trodden ground of geography, navigation and GPS technology, invent a completely new patentable pin pointing system.
I suspect that an amalgam of technologies will be used, [and some even pinched?] to create the proverbial horse designed by a committee.
I look forward to the happy day I am proven wrong....genuinely.

BailMeOut

Curly Judge wrote: »

Thanks!
Mostly I agree with your analysis and the proposed system is surely an improvement on the previous postal code dinosaur.
But....are you in all seriousness suggesting that gallant little Ireland is going to go out and, on the well trodden ground of geography, navigation and GPS technology, invent a completely new patentable pin pointing system.
I suspect that an amalgam of technologies will be used, [and some even pinched?] to create the proverbial horse designed by a committee.
I look forward to the happy day I am proven wrong....genuinely.

Loc8 did it. They basically have some formula that one would assume they own and have patented that converts a longitude/latitude co-ordinate to a simple small easy to remember code. If this is done right you should be able to revert the code back to the exact co-ordinates using maths and not having to look-up a database.

I wish I was on the committee that got to develop this!

Delphic

BailMeOut wrote: »

Loc8 did it. They basically have some formula that one would assume they own and have patented that converts a longitude/latitude co-ordinate to a simple small easy to remember code. If this is done right you should be able to revert the code back to the exact co-ordinates using maths and not having to look-up a database.

I wish I was on the committee that got to develop this!

design is already done - A65 B2CD

a65b2cd

BailMeOut wrote: »

Loc8 did it. They basically have some formula that one would assume they own and have patented that converts a longitude/latitude co-ordinate to a simple small easy to remember code. If this is done right you should be able to revert the code back to the exact co-ordinates using maths and not having to look-up a database.

I wish I was on the committee that got to develop this!

Another approach is to have two fields in the database: one containing the postcode and another the geo-coordinates. This way any existing error in the coordinates could be corrected without having to amend the postcode. Presumably access to Geodirectory has been negotiated as the basis for forming the new database.

Sam Russell

Curly Judge wrote: »

If an Irish hospital wants a CAT scanner in the morning, what does it do?
Form a committee that sits for 10 years and draws up the plans for a new, never before seen or heard of, scanner.
Or... buys, leases or licences the use of a scanner from a private [dirty word, I know] company.
Do the public expect the private company to provide the service free of charge?
I would suggest that what the public want is the scanner provided and operated at a reasonable, competitive price and [equally important] that the bloody thing does what it says on the tin.

I think that using the Irish health system as an example is likely to be unproductive. The National Children's Hospital is a case in point. Before it, we had the Tallagh Hospital saga. Then we have the drugs price issue where Ireland pays multiples of the UK or Spannish price for drugs.

No, don't use Irish health issues as an argument for any form of procurement.

Sam Russell

a65b2cd wrote: »

Another approach is to have two fields in the database: one containing the postcode and another the geo-coordinates. This way any existing error in the coordinates could be corrected without having to amend the postcode. Presumably access to Geodirectory has been negotiated as the basis for forming the new database.

That is what would be in the current proposal.

Database

Record - GPRN NO; Address; Post code; Geo co-ordinates.

BailMeOut

Sam Russell wrote: »

That is what would be in the current proposal.

Database

Record - GPRN NO; Address; Post code; Geo co-ordinates.

Can the co-ordinates be calculated just from the post code or must you have access to the database to do a look-up?

BailMeOut

BailMeOut wrote: »

Can the co-ordinates be calculated just from the post code or must you have access to the database to do a look-up?

Very unlikely, with only four characters to play with, you'll have to use the database to do a lookup either way.

SpaceTime

BailMeOut wrote: »

Can the co-ordinates be calculated just from the post code or must you have access to the database to do a look-up?

We don't know yet as there have been no details announced.

Delphic

Deleted User wrote: »

Very unlikely, with only four characters to play with, you'll have to use the database to do a lookup either way.

Exactly. Although an eighth character might do it, I suppose.

Victor

BailMeOut wrote: »

Can the co-ordinates be calculated just from the post code or must you have access to the database to do a look-up?

No. How could it?

The code is made up of the following:

Letter D = County *
Two Numbers 04 = current or new postal zone, with a leading zero added for 1-9 *
Letter = splits the above layer in 24 **
Number = splits the above layer in 8 ***
Letter = splits the above layer in 24 **
Letter = splits the above layer in 24 **

That gives a potential 24 x 8 x 8 x 24 * 8* 24 *24 = 169,869,312 addresses, perfectly adequate for 4.5 million people, and about 2 million existing address.

To get working coordinates for postal work, using the national grid you would need 25 x 100 x 100 x 1000 x 1000 = 260,000,000,000 and a typical post code would be F1234567890. However only 70,000,000,000 would be valid in the Republic of Ireland (some would be in northern Ireland, possibly some in Britain, the rest at sea). However, it would only be good enough to get you to the front door / public letter box and wouldn't provide unique codes with the likes of apartment or office blocks.

* While we have 26 counties and 26 letters in the alphabet, Longford will want LD9 a9aa, not Q99 a9aa. It they go for two letter counties, then each might only have 10 postal zones.
** Assuming I and O aren't used - to avoid confusion.
*** Assuming 1 and 0 aren't used - to avoid confusion / retained for system use.

Victor

Just another way of looking at things, this is the amount of road in each council area, give or take. Some of the information is a few years out of date, but it will be within a few per cent.

Council Motorway National Road Regional Road Local Road Total
Carlow 24 55 186 948 1,212
Cavan 0 129 399 2,470 2,998
Clare 32 202 633 3,399 4,266
Cork City 0 21 41 350 412
Cork County 51 467 1,402 10,318 12,237
Donegal 0 305 689 5,298 6,292
Dublin City 6 1 215 931 1,153
Dún Laoghaire-Rathdown 18 17 108 550 693
Fingal 43 12 227 1,019 1,302
Galway City 0 17 36 245 298
Galway County 62 384 861 5,602 6,909
Kerry 0 430 530 3,872 4,832
Kildare 108 26 482 1,613 2,229
Kilkenny 68 136 412 2,542 3,158
Laois 67 100 340 1,725 2,232
Leitrim 0 57 336 1,770 2,162
Limerick City 0 1 35 144 180
Limerick County 27 165 480 2,929 3,601
Longford 0 103 155 1,340 1,598
Louth * 40 85 126 1,144 1,395
Mayo 0 396 656 5,497 6,549
Meath 87 130 610 2,610 3,437
Monaghan 0 112 302 2,122 2,536
North Tipperary 73 105 410 2,141 2,729
Offaly 15 103 389 1,639 2,146
Roscommon 21 231 373 3,357 3,982
Sligo 0 150 223 2,271 2,644
South Dublin 15 39 100 732 886
South Tipperary 49 107 485 2,341 2,982
Waterford City 0 3 32 137 172
Waterford County * 0 104 339 2,016 2,459
Westmeath 56 118 310 1,847 2,332
Wexford 25 146 457 2,756 3,384
Wicklow 17 75 422 1,540 2,054

* Suspect data / data gaps

So, in a city area, you could have 6-40 address per metre of road. For rural areas, eash code would represent 1-14 metres of road.

Note, roads tend to have at least two sides and you will want to keep perhaps two thirds of the system for expansion, system addresses, vanity addresses, obscenities, etc. - I can see Ross O'Carroll Kelly looking for D18 R0CK. Cork would need to be looked at though - big county with lots of road.

Council Total (km) Total (m) a 9 9 a 9 a a Inverse
Waterford City 172 172,000 W 21,500 2,688 112 14 0.58 0.02 41.15
Limerick City 180 180,000 L 22,500 2,813 117 15 0.61 0.03 39.32
Galway City 298 298,000 G 37,250 4,656 194 24 1.01 0.04 23.75
Cork City 412 412,000 C 51,500 6,438 268 34 1.40 0.06 17.18
Dublin City 1,153 1,153,000 D 144,125 18,016 751 94 3.91 0.16 6.14
Dún Laoghaire-Rathdown 693 693,000 DR DR 86,625 3,609 451 18.80 0.78 1.28
South Dublin 886 886,000 DS DS 110,750 4,615 577 24.03 1.00 1.00
Carlow 1,212 1,212,000 CW CW 151,500 6,313 789 32.88 1.37 0.73
Fingal 1,302 1,302,000 FL FL 162,750 6,781 848 35.32 1.47 0.68
Louth * 1,395 1,395,000 LH LH 174,375 7,266 908 37.84 1.58 0.63
Longford 1,598 1,598,000 LD LD 199,750 8,323 1,040 43.35 1.81 0.55
Wicklow 2,054 2,054,000 WW WW 256,750 10,698 1,337 55.72 2.32 0.43
Offaly 2,146 2,146,000 OY OY 268,250 11,177 1,397 58.21 2.43 0.41
Leitrim 2,162 2,162,000 LM LM 270,250 11,260 1,408 58.65 2.44 0.41
Kildare 2,229 2,229,000 KE KE 278,625 11,609 1,451 60.47 2.52 0.40
Laois 2,232 2,232,000 LS LS 279,000 11,625 1,453 60.55 2.52 0.40
Westmeath 2,332 2,332,000 WH WH 291,500 12,146 1,518 63.26 2.64 0.38
Waterford County * 2,459 2,459,000 WD WD 307,375 12,807 1,601 66.70 2.78 0.36
Monaghan 2,536 2,536,000 MN MN 317,000 13,208 1,651 68.79 2.87 0.35
Sligo 2,644 2,644,000 SO SO 330,500 13,771 1,721 71.72 2.99 0.33
North Tipperary 2,729 2,729,000 TN TN 341,125 14,214 1,777 74.03 3.08 0.32
South Tipperary 2,982 2,982,000 TS TS 372,750 15,531 1,941 80.89 3.37 0.30
Cavan 2,998 2,998,000 CN CN 374,750 15,615 1,952 81.33 3.39 0.30
Kilkenny 3,158 3,158,000 KK KK 394,750 16,448 2,056 85.67 3.57 0.28
Wexford 3,384 3,384,000 WD WD 423,000 17,625 2,203 91.80 3.82 0.26
Meath 3,437 3,437,000 MH MH 429,625 17,901 2,238 93.23 3.88 0.26
Limerick County 3,601 3,601,000 LK LK 450,125 18,755 2,344 97.68 4.07 0.25
Roscommon 3,982 3,982,000 RN RN 497,750 20,740 2,592 108.02 4.50 0.22
Clare 4,266 4,266,000 CE CE 533,250 22,219 2,777 115.72 4.82 0.21
Kerry 4,832 4,832,000 KY KY 604,000 25,167 3,146 131.08 5.46 0.18
Donegal 6,292 6,292,000 DL DL 786,500 32,771 4,096 170.68 7.11 0.14
Mayo 6,549 6,549,000 MO MO 818,625 34,109 4,264 177.65 7.40 0.14
Galway County 6,909 6,909,000 GY GY 863,625 35,984 4,498 187.42 7.81 0.13
Cork County 12,237 12,237,000 CK CK 1,529,625 63,734 7,967 331.95 13.83 0.07

larchill

SpaceTime wrote: »

Because we are not implementing a simple postal sorting aid which is what most European post codes are.

What would be the point of it? The problem in Ireland is an inability to find individual houses.

the proposed system gives each building a unique identifier in a country with very vague and confusing addresses and many non unique addresses.

It's a good solution to an Irish problem and it has been debated over and over on this thread for years.

I think the conclusions reached on this thread are fairly similar to the conclusions reached by the department even if the minutia of how it works might be argued about, theres a consensus that it absolutely needs to be a level of granularity that can identify a single building.

The system used in Scandinavia isn't aimed at doing what this coding system will do.

The old numeric postcode systems used in most countries only really were there to make it possible for old automatic letter sorters to read the final line of addresses to send an item to the correct local area. They are useless for GPS.

What's being proposed here is a world first.

Don't forget also that other places generally name streets/roads & number houses. NI has all roads named & houses are numbered. Go to Spain, France, Italy, etc & the situation is similar. We're unique in not naming & numbering. Even in smaller towns & villages numbering is not generally used. A unique code as proposed will 'kill 2 birds with 1 stone' - no need to go out & name all those roads & then as for numbering houses ...

Delphic

larchill wrote: »

Don't forget also that other places generally name streets/roads & number houses. NI has all roads named & houses are numbered. Go to Spain, France, Italy, etc & the situation is similar. We're unique in not naming & numbering. Even in smaller towns & villages numbering is not generally used. A unique code as proposed will 'kill 2 birds with 1 stone' - no need to go out & name all those roads & then as for numbering houses ...

Yep. It should be easy. Make the postal zones random letters/numbers so can't be linked with county or region in any way and avoid rows of who's called what.
Then take one house and put a code on it. Take the next house and put a code on that, then the next one, and the next one. Repeat 2.2m times and the job is done.

Sigourney

Leonard Shelby wrote: »

Read the press release. Everyone will be given their postcode in Spring 2015. Capita will manage the administration for 10 years.

Something in today's Inglipendent about Capita:
'Less than two weeks since the Home Office anti-immigration vans were banned by the advertising watchdog for using “misleading” statistics, the UK Border Agency has come under fire for telling an anti-racism campaigner and an immigration adviser to leave the country in a text.

On behalf of UKBA, private contractor Capita sent leading campaigner Suresh Grover a text telling him he had no right to live here. The same text was sent to Bobby Chan, an Immigration Caseworker at Central London Community Law.'

http://www.independent.co.uk/news/uk/antiracism-campaigner-and-immigration-caseworker-sent-go-home-text-messages-by-home-office-8886200.html

Victor

The British (not sure about Canada) system is capable of being house specific if you simply put the building number with the post code.

larchill wrote: »

Don't forget also that other places generally name streets/roads & number houses. NI has all roads named & houses are numbered. Go to Spain, France, Italy, etc & the situation is similar. We're unique in not naming & numbering. Even in smaller towns & villages numbering is not generally used. A unique code as proposed will 'kill 2 birds with 1 stone' - no need to go out & name all those roads & then as for numbering houses ...

Actually, an awful lot of rural roads do have names, just that they are poorly recorded and signed.

Delphic wrote: »

Yep. It should be easy. Make the postal zones random letters/numbers so can't be linked with county or region in any way and avoid rows of who's called what.

Actually, that can be a dis-service. Being able to check that the post code at least looks like it is going to the right place or at least will get to the right sorting office is useful.

marmurr1916

SpaceTime wrote: »

Dublin postal districts and quite possibly the Cork ones were introduced in 1917 and tweaked a bit over the years.

Cork was divided up into postal districts, but nobody ever used them for some reason. They're on the street signs and they come in on your address on the TV Licence demands.

The London ones were sometime in the late 1800s.

Basically in that system you'd a delivery office in each district. So, it just meant that in a manual sorting system you'd box 1,2,3,4,5 etc

London being a lot bigger and having a lot more postal centres, used letters for South, North, East, West etc too which were just kept in place for the new postcodes.

A similar system was used for Glasgow, Liverpool and other large cities in the 19th century.

These lettered postal districts were maintained until 1934 when they were replaced by numbered districts, with no letters used.

In London, the lettered districts were subdivided by the addition of numbers (eg. SW1).

SpaceTime wrote: »

Originally, the Dublin codes were actually D1,D2,D3 etc as it was part of the Royal Mail system. At least that's what the articles on Wiki say.

The original Dublin codes were simply numbers, with no preceding letter D.

Dublin was originally divided into postal districts in 1917.

The only major modifications to the system have been the addition of new postal districts as the city has expanded and the innovation of adding Dublin 6W (done so that residents of that area wouldn't have to use Dublin 26 and thus be adjacent to Tallaght, Dublin 24).

Larger cities and towns in the UK were divided into numbered postal districts (1, 2, 3, 4 etc) from 1934 onwards, much like Dublin is today, without any preceding letters.

For example, Liverpool L1 is the current Liverpool postal district 1. Before the 1950s it was simply Liverpool 1, similar to today's Dublin system.

The current UK postcode system was only introduced from 1959 onwards.

Some existing postal districts were incorporated into the new system, others were completely changed:

Adaptation of earlier systems into national system
When the national postcode system was introduced, many existing postal districts were incorporated into it, so that postcodes in Toxteth (Liverpool 8) start with L8. The districts in both Manchester and Salford gained "M" postcodes, so "Salford 7" became M7, etc. In other cases, the district numbers were replaced with new unrelated numbers. The old coding lives on in a small number of street signs with "Salford 7" etc., at the bottom. In Glasgow C1 became G1, W1 became G11, N1 became G21, E1 became G31, S1 became G41, SW1 became G51, and so on. In London the 1917 postal districts mapped directly to the new postcode districts. The remaining 60% of Greater London was allocated postcodes under the national plan.

This Wikipedia article, if read carefully, gives more accurate information:

http://en.wikipedia.org/wiki/Postcodes_in_the_United_Kingdom

SpaceTime

larchill wrote: »

Don't forget also that other places generally name streets/roads & number houses. NI has all roads named & houses are numbered. Go to Spain, France, Italy, etc & the situation is similar. We're unique in not naming & numbering. Even in smaller towns & villages numbering is not generally used. A unique code as proposed will 'kill 2 birds with 1 stone' - no need to go out & name all those roads & then as for numbering houses ...

There's still a lot of unnumbered housing in parts of rural Britain. Not to dissimilar to here really

antoinolachtnai

BailMeOut wrote: »

Can the co-ordinates be calculated just from the post code or must you have access to the database to do a look-up?

In practice, you always have to look up in the database. A driver or other service company will always want to check that the code corresponds with other address information.

A driver or service provider will just not agree to deliver to an unqualified coordinate. To do so would just be too error-prone.

Sam Russell

Victor wrote: »

No. How could it?

The code is made up of the following:

Letter D = County *
Two Numbers 04 = current or new postal zone, with a leading zero added for 1-9 *
Letter = splits the above layer in 24 **
Number = splits the above layer in 8 ***
Letter = splits the above layer in 24 **
Letter = splits the above layer in 24 **

That gives a potential 24 x 8 x 8 x 24 * 8* 24 *24 = 169,869,312 addresses, perfectly adequate for 4.5 million people, and about 2 million existing address.

To get working coordinates for postal work, using the national grid you would need 25 x 100 x 100 x 1000 x 1000 = 260,000,000,000 and a typical post code would be F1234567890. However only 70,000,000,000 would be valid in the Republic of Ireland (some would be in northern Ireland, possibly some in Britain, the rest at sea). However, it would only be good enough to get you to the front door / public letter box and wouldn't provide unique codes with the likes of apartment or office blocks.

* While we have 26 counties and 26 letters in the alphabet, Longford will want LD9 a9aa, not Q99 a9aa. It they go for two letter counties, then each might only have 10 postal zones.
** Assuming I and O aren't used - to avoid confusion.
*** Assuming 1 and 0 aren't used - to avoid confusion / retained for system use.

You do not have to do it that way. Do not use counties, use towns (or townlands).

Have the first thee characters point to a town. Say the 100 or so largest towns would be given a number codes, depending on size. Dublin would be special.

The space around each town would be divided up into tiles which would be numbered by some algorith that removes rude combinations, and assigns the order of the tiles, so that the whole country is covered without duplication. Each tile would then be divided down to 10m or so resolution. Redundancy would give an element of error checking.

However, a look-up database would be much better, but would require mantenance, but could give resolution down to single buildings.

BailMeOut

how will SatNav devices work if it goings to depend on a database? Surely we will want to encourage Garmin/Tom Tom / etc to include the option to look-up the post code but if it needs to connect to a database then this cannot work unless the SatNav device can store every address and post code in the country.