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://comtrade.un.org/data/doc/api/
ct_commodity_lookup( search_terms, return_code = FALSE, return_char = FALSE, verbose = TRUE, ignore.case = TRUE, ... )
search_terms | Commodity names or commodity codes, as a char or numeric vector. |
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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. |
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
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... | additional args to be passed along to |
A list or character vector of commodity descriptions and/or commodity codes that are matches with the elements of "search_terms".
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 this great tutorial by Gloria Li and Jenny Bryan http://stat545.com/block022_regular-expression.html
# Look up commodity descriptions related to "halibut" ct_commodity_lookup("halibut", return_code = FALSE, return_char = FALSE, verbose = TRUE)#> $halibut #> [1] "030221 - Fish; halibut (reinhardtius hippoglossoides, hippoglossus hippoglossus, hippoglossus stenolepis), fresh or chilled (excluding fillets, livers, roes and other fish meat of heading no. 0304)" #> [2] "030331 - Fish; halibut (reinhardtius hippoglossoides, hippoglossus hippoglossus, hippoglossus stenolepis), frozen (excluding fillets, livers, roes and other fish meat of heading no. 0304)" #># Look up commodity codes related to "shrimp". ct_commodity_lookup("shrimp", return_code = TRUE, return_char = FALSE, verbose = TRUE)#> $shrimp #> [1] "030613" "030616" "030617" "030623" "030626" "030627" "030635" "030636" #> [9] "030695" "160520" "160521" "160529" "160540" #>