The Comtrade API requires that searches for specific commodities be done using commodity codes. This is a helper function for querying the Comtrade commodity database. It takes as input a vector of commodities or commodity codes. Output is a list or vector of commodity descriptions or codes associated with the input search_terms. For use with the UN Comtrade API, full API docs can be found at https://unstats.un.org/wiki/display/comtrade/
Usage
ct_commodity_lookup(
search_terms,
return_code = FALSE,
commodity_classification = "HS",
type = "goods",
return_char = FALSE,
verbose = TRUE,
ignore.case = TRUE,
update = FALSE,
...
)Arguments
- search_terms
Commodity names or commodity codes, as a char or numeric vector.
- return_code
Logical, if set to FALSE, the function will return a set of commodity descriptions along with commodity codes (as a single string for each match found), if set to TRUE it will return only the commodity codes. Default value is FALSE.
- commodity_classification
The trade classification scheme. Possible values for goods:
c('HS','S1','S2','S3','S4','SS','B4','B5'); for services:c('EB02','EB10','EB10S','EB'). Default: 'HS'.- type
The type of returned trade data. Possible values: 'goods' for trade in goods, 'services' for trade in services. Default: 'goods'.
- return_char
Logical, if set to FALSE, the function will return the matches as a named list, if set to TRUE it will return them as a character vector. Default value is FALSE.
- verbose
Logical, if set to TRUE, a warning message will print to console if any of the elements of input "search_terms" returned no matches (message will indicate which elements returned no data). Default is TRUE.
- ignore.case
logical, to be passed along to arg ignore.case within
grepl. Default value is TRUE.- update
If TRUE, downloads possibly updated reference tables from the UN. Default: FALSE.
- ...
additional args to be passed along to
grepl.
Value
A list or character vector of commodity descriptions and/or commodity codes that are matches with the elements of "search_terms".
Details
This function uses regular expressions (regex) to find matches within the commodity DB. This means it will treat as a match any commodity description that contains the input search term. For more on using regex within R, see https://stat.ethz.ch/R-manual/R-devel/library/base/html/regex.html