Reply to: Complete UK Postcode Database on Wikileaks

[Muttley08]

This was what I was thinking about - can happen in blocks of flats or on big industrial sites...


# Some buildings can contain delivery addresses with different postcodes. High-rise residential buildings are a good example of these. As far as the Code-Point dataset is concerned these are called Vertical Streets, and their boundaries are recorded as regular squares. These are clearly visible when the postcode boundaries are mapped.

This is referring to code-point and what they look like as a polygon layer - but might be what you're finding...either that or PO Boxes...or both...

[Spacecadet]

Military?

Nah... a couple, some or lots of red vans and lorrys near them all
Proof that they're post boxes

[Clippy]

Based on a small sample size, big buildings by the looks of it.

And?

Military?

[Sysman]

Bugs in the database by the looks of it. The one off Scilly corresponds to a dozen postcodes near BD985YA in the file with a latitude and longitude of 49.766731, -7.55729. I haven't checked the other one, as I haven't created a reverse search yet and I'm laboriously binary chopping the data manually to find them. There also appear to be something like 200,000 postcodes on the file with no (i.e. 0,0) latitude and longitude at all. Still, it is free

I'd guess that BD985YA is a PO Box. Bradford and Bingley for example.

[Muttley08]

Ordnance Survey do have some complex postcodey thing that doesn't have geo-ref's - been years since I used it in anger - so can't remember exactly what they're used for...

If you can be bothered...have a look for the codepoint user guide - skimmed it...but can't find the info...

[Spacecadet]

Based on a small sample size, big buildings by the looks of it.

And?

[TimberWolf]

about the same as in the version you have

The PZONE file is used for mapping postcodes to statistical regions. It is NOT an address file.
There are plenty of postcodes which one one reason or another need to be excluded from these statistical regions. Most commonly it's because the postcode relates to a postbox.

Like I said, look closely. Take one of your postcodes which google maps finds but is listed without a lat/long. Stick it in google maps, switch on the satelite view and zoom in.
Then tell me what is common amongst the vast majority of those postcodes

Based on a small sample size, big buildings by the looks of it.

[Muttley08]

I work in this area - and guessing if there are statistical boundaries on there, I know where this has come from...if I'm right they re-sell this data for quite a lot of money..

Update - Just opened it...looks like too many NHS identifiers to be who I thought it was - and most UK mainland orgs don't use Lat / Long

[Spacecadet]

Do you recall how many were geographically untied in your paid for version?

about the same as in the version you have

The PZONE file is used for mapping postcodes to statistical regions. It is NOT an address file.
There are plenty of postcodes which one one reason or another need to be excluded from these statistical regions. Most commonly it's because the postcode relates to a postbox.

Like I said, look closely. Take one of your postcodes which google maps finds but is listed without a lat/long. Stick it in google maps, switch on the satelite view and zoom in.
Then tell me what is common amongst the vast majority of those postcodes

[TimberWolf]

Look closely, you'll see why assigning them geographical values in the PZONE file is nonsense

Do you recall how many were geographically untied in your paid for version?

[Spacecadet]

Based on small a random sample, the postcodes appear to be 'geographically tied' in Google maps no problem.

Look closely, you'll see why assigning them geographical values in the PZONE file is nonsense

[TimberWolf]

Those will be the non-geographically tied postcodes
Try reading the thread

Based on small a random sample, the postcodes appear to be 'geographically tied' in Google maps no problem.

[Spacecadet]

There also appear to be something like 200,000 postcodes on the file with no (i.e. 0,0) latitude and longitude at all. Still, it is free

Those will be the non-geographically tied postcodes
Try reading the thread

[TimberWolf]

Out of interest, what are the ones that are in the sea (1 off SW coast of Ireland, one SW of Scilly)?

Bugs in the database by the looks of it. The one off Scilly corresponds to a dozen postcodes near BD985YA in the file with a latitude and longitude of 49.766731, -7.55729. I haven't checked the other one, as I haven't created a reverse search yet and I'm laboriously binary chopping the data manually to find them. There also appear to be something like 200,000 postcodes on the file with no (i.e. 0,0) latitude and longitude at all. Still, it is free

[Moscow Mule]

I've plotted all 1.8 million postcodes in that file on a map. Very pretty.

http://img21.imageshack.us/img21/2605/postcodes.jpg

Spot the national parks - cool...