index_postcodes: Create an Index for an ONS NSPL postcode database

In DHatziioanou/simpleepi: Simplifying functions to improve the ease and speed of basic epidemiological analysis

Create an Index for an ONS NSPL postcode database

Description

Creates an index of a postcode database file using the first letters and first number from within the postcode. This has been designed for use with the NSPL database of UK postcodes and will not work for postcodes which do not start with letters followed by numbers.

Usage

index_postcodes(postcode_path, colname, name, exclude)

Arguments

postcode_path	path to folder containing multiple postcode csv files or a single csv file. Eg for ONS NSPL this could be either file.path("NSPL_FEB_2019_UK", "Data", "multi_csv") from where the ONS data was extracted if using the multi_csv files or file.path("NSPL_FEB_2019_UK", "Data", "NSPL_FEB_2019_UK.csv") if using the full database file. Using multi_csv files can overcome insufficient memory barriers.
colname	column name within database csv file(s) with postcode for postcode matching (optional). Default is the first column name within the database.
name	name to call the index (optional). Default is "Index".
exclude	string pattern within files to exclude when using a folder as postcode_path (optional).

Value

Returns a postcode database Index using the first letters from the file names and the first digits of the numbers within the postcodes as a data.frame object. Saves the Index file to the location of the postcode database.

Author(s)

Diane Hatziioanou

Examples

# Index <- index_postcodes(postcode_path)

# Index_ONS <- index_postcodes("C:/.../NSPL_FEB_2019_UK/Data/multi_csv/)

# Index_ONS <- index_postcodes(
    # file.path(path, "NSPL_FEB_2019_UK, "Data ,"multi_csv"),
    # exclude = "Readme.csv")

# Index_file <- index_postcodes(file.path(path, "2020 database, "Reference.csv"),
    # colname = "pcd", name = "Reference_index")

# Create an index if necessary or read in if already there
# if (!file.exists(file.path(NSPL_csvs,"Index.csv"))) {
# Index <- index_postcodes(NSPL_csvs)
# } else {
#   Index <- fread(file.path(NSPL_csvs,"Index.csv"))
#  }

DHatziioanou/simpleepi documentation built on Sept. 24, 2024, 5:25 a.m.