Combine two ID values to create a single ID number
od_id_szudzik(x, y, ordermatters = FALSE)
od_id_max_min(x, y)
od_id_character(x, y)a vector of numeric, character, or factor values
a vector of numeric, character, or factor values
logical, does the order of values matter to pairing, default = FALSE
In OD data it is common to have many 'oneway' flows from "A to B" and "B to A". It can be useful to group these an have a single ID that represents pairs of IDs with or without directionality, so they contain 'twoway' or bi-directional values.
od_id* functions take two vectors of equal length and return a vector of IDs,
which are unique for each combination but the same for twoway flows.
the Szudzik pairing function, on two vectors of equal length. It returns a vector of ID numbers.
This function superseeds od_id_order as it is faster on large datasets
od_oneway
Other od:
od_to_odmatrix(),
odmatrix_to_od()
(d = od_data_df[2:9, 1:2])
#> geo_code1 geo_code2
#> 2 E02002404 E02006875
#> 3 E02006875 E02006875
#> 4 E02006876 E02006875
#> 5 E02006861 E02002392
#> 6 E02006875 E02002392
#> 7 E02002392 E02006875
#> NA <NA> <NA>
#> NA.1 <NA> <NA>
(id = od_id_character(d[[1]], d[[2]]))
#> [1] "E02002404 E02006875" "E02006875 E02006875" "E02006875 E02006876"
#> [4] "E02002392 E02006861" "E02002392 E02006875" "E02002392 E02006875"
#> [7] "NA NA" "NA NA"
duplicated(id)
#> [1] FALSE FALSE FALSE FALSE FALSE TRUE FALSE TRUE
od_id_szudzik(d[[1]], d[[2]])
#> [1] 5 6 11 29 27 27 NA NA
od_id_max_min(d[[1]], d[[2]])
#> [1] 4 5 8 19 17 17 NA NA