Code-Point Open support

The data structure of Code-Point Open is the same as Code-Point but without the following attribution:

• Northern Ireland postcode information (BT Postcode Area file);
• PO Box indicator;
• Total number of delivery points;
• Delivery points;
• Domestic delivery points;
• Non-domestic delivery points;
• PO Box delivery points;
• Matched address premises;
• Unmatched delivery points; and
• Postcode type.

Code-Point Open contains postcodes georeferenced to the notional centre of the postcode unit.

However, Code-Point Open does not contain information that can tell you if the postcode is a PO Box or Large or Small user for example.

You will not be able to confidently identify an area of houses from a Royal Mail sorting office for example.

It can take some time for a new postcode to work its way through the system into Code-Point Open. Until our surveyors have visited the area to complete the very precise large-scale mapping, we allocate a calculated map reference to the postcode that, depending on the level of development in the area, can be somewhat inaccurate. When this has been done, a positional quality indicator in the Code-Point Open record makes it clear that the coordinates provided are temporary, and will be improved to a full quality match as soon as possible.

Code-Point Open includes 120 postcode areas in England, Scotland and Wales, but does not include the postcode areas for the Isle of Man, the Channel Islands and Northern Ireland.

The product is updated every three months (February, May, August and November).

More often than not, this is the result of the recoding of an area by Royal Mail. This can happen for various reasons, usually because there are more postcodes required than there is capacity within the higher-level aggregations of postcodes, known as postcode sectors, districts and areas. The postcodes will therefore change, for example, from RG1 1AA to RG10 1AA.

Changes to Royal Mail postcodes may result in some postcodes being deleted and therefore no longer represented in the product.

The postcodes in Code-Point Open and Code-Point are for ‘live’ postcodes only that Royal Mail are currently delivering too. If Royal Mail aren’t delivering to these addresses then the postcodes won’t be in any of the Ordnance Survey postcode products. They will be reinstated if, and when, Royal Mail deliver post to those addresses again.

The object definitions are taken from ONS Codes database

It is important to understand the difference between accuracy and resolution. Usually, the question is really asking about resolution.

Code-Point Open is created by taking the average of the coordinates of all the individual addresses in a postcode (provided we have any of sufficient quality), then snapping to the nearest of those addresses. Code-Point Open then delivers the coordinates of that address, as representative of the whole postcode, to a resolution of 1 metre.

The accuracy of a Code-Point Open record could be expressed as, that the coordinated position will always be within the notional geographical extent of the postcode. The accuracy of each postcode unit coordinate pair is defined by the positional quality indicator (PQI) which provides a quality statement of a Code-Point record.

When used in an address the inward code (incode) should be separated from the outward code (outcode) by a single space, however, within the supplied Code-Point products there may be 0, 1 or 2 spaces between these two elements.

The postcode field is set at seven characters. The varying number of spaces in this field is determined by the number of characters in the postcode and parameters within the production system that stipulate the use of seven characters. Instructions are provided within the User Guide (link) for how to create single space postcodes.

This is because Unitary authorities, London Boroughs and Metropolitan Districts do not sit within a County - they are independent local government boundaries. Some postcodes will show three tier Admin_County_Codes, Admin_District_codes, Admin_Ward_codes, others will just have a 2 tier UA/LB or Met District code (DC) and the Ward code (WC).

You can see whether a postcode is in a 2 or 3 tier area by looking at the OS OpenData viewer and selecting the boundary layers in the top right of the map acreen.

Code-Point Open contains five admin ward codes for postcodes on the Isles of Scilly. These have been issued by ONS for statistical purposes only, because there are no wards on the Isles of Scilly. The Codelist.xls file supplied with Code-Point Open is generated from Boundary-Line. Boundary-Line does not contain these ward codes as they do not exist for political purposes. Therefore, these codes are not available in the Codelist.xls file supplied in the Doc folder with Code-Point Open. All other ward codes should exist in both Code-Point Open and the Codelist.xls file.

1. Unzipping the data
Code-Point Open is delivered zipped for speed of download. In order to use the data, it must first be unzipped. The user should save the zipped file to a location, and from here unzip it using WinZip, or an equivalent piece of software. All of the CSV data files can be found within the ‘data’ folder of the unzipped ‘Code-Point Open’ folder, e.g. C:\temp\Code-Point Open\data.

2. Combining (concatenating) multiple CSV files
After unzipping the files, it is beneficial to combine all CSV files together to ensure that the user does not have to follow the import procedure for each of the individual files, which can be time consuming and repetitive. Here is an explanation of one way to combine all the individual CSV files in to a single file by using a .bat batch file.
To use the batch function:

• Copy the following text and paste it into a new Notepad document: copy *.csv outputfile.csv
  N.B., outputfile.csv can be any user defined file name with the extension .csv, e.g. CPO_National.csv
• Save the Notepad document with the file extension .bat (e.g. combine.bat) in the same directory as the CSV files unzipped in Section 1. (e.g. C:\Temp\Code-Point Open\data).
• Close the .bat file, and navigate to the directory where it was saved (e.g. C:\Temp\Code-Point Open\data). Double click on the .bat file (i.e. merge.bat) and an MS-DOS window will appear, once the process is complete the MS-DOS screen will close automatically.
• If you navigate to the location where all of the CSV files were originally downloaded and where the .bat file was created, you will notice that there is a new CSV file with the user defined name inserted in the .bat file.

Note: The CSV file that is created comes to approximately 150Mb, and 1.7 million records. If this is opened in Microsoft Excel only the first 65,536 records can be seen as the software cannot display more than this number of records.