The goal of this tutorial is to learn how to introduce numbers in a string, filling with zeroes up to a given number. This is useful when creating filenames.
# We want to use a numerical vector to create strings
my_vector <- as.character(1:20)
my_vector## [1] "1" "2" "3" "4" "5" "6" "7" "8" "9" "10" "11" "12" "13" "14"
## [15] "15" "16" "17" "18" "19" "20"# However in strings, the order doesn't follow the numerical logic
# First all numbers starting with 1 will appear, then the ones starting with 2, and so on
order(my_vector)## [1] 1 10 11 12 13 14 15 16 17 18 19 2 20 3 4 5 6 7 8 9my_vector[order(my_vector)]## [1] "1" "10" "11" "12" "13" "14" "15" "16" "17" "18" "19" "2" "20" "3"
## [15] "4" "5" "6" "7" "8" "9"# If we want the strings to follow the same order than the numbers we need to make changes
# We will introduce zeroes in front of all numbers until the length of the biggest number
# Now the numbers will look like 01, 02, 03, 04, 05, etc
my_vector <- 1:20
my_vector <- as.character(formatC(my_vector, width=2, flag="0"))
my_vector## [1] "01" "02" "03" "04" "05" "06" "07" "08" "09" "10" "11" "12" "13" "14"
## [15] "15" "16" "17" "18" "19" "20"# And now the original order is kept
order(my_vector)## [1] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20my_vector[order(my_vector)]## [1] "01" "02" "03" "04" "05" "06" "07" "08" "09" "10" "11" "12" "13" "14"
## [15] "15" "16" "17" "18" "19" "20"# We repeat the same exercise with numbers containing 3 cifers
my_vector <- 1:100
my_vector <- as.character(formatC(my_vector, width = 3, flag = "0"))
my_vector## [1] "001" "002" "003" "004" "005" "006" "007" "008" "009" "010" "011"
## [12] "012" "013" "014" "015" "016" "017" "018" "019" "020" "021" "022"
## [23] "023" "024" "025" "026" "027" "028" "029" "030" "031" "032" "033"
## [34] "034" "035" "036" "037" "038" "039" "040" "041" "042" "043" "044"
## [45] "045" "046" "047" "048" "049" "050" "051" "052" "053" "054" "055"
## [56] "056" "057" "058" "059" "060" "061" "062" "063" "064" "065" "066"
## [67] "067" "068" "069" "070" "071" "072" "073" "074" "075" "076" "077"
## [78] "078" "079" "080" "081" "082" "083" "084" "085" "086" "087" "088"
## [89] "089" "090" "091" "092" "093" "094" "095" "096" "097" "098" "099"
## [100] "100"In this tutorial we have learnt how to add numbers to a string adding the proper amount of zeroes to keep the original order.