I have downloaded a table of stream diversion data ("df_download"). The column names of this table are primarily taken from the ID numbers of the gauging stations.
I want to conditionally replace the ID numbers that have been used for column names with text for the station names, which will help make the data more readable when I'm sharing the results. I created a table ("stationIDs") with the ID numbers and station names to use as a reference for changing the column names of "df_download".
I can replace the column names individually, but I want to write a loop of some kind that will address all of the columns of "df_download" and change the names of the columns referenced in the dataframe "stationIDs".
An example of what I'm trying to do is below.
Downloaded Data ("df_download")
A portion of the downloaded data is similar to this:
df_downloaded <- data.frame(Var1 = seq(as.Date("2012-01-01"),as.Date("2012-12-01"), by="month"),
Var2 = sample(50:150,12, replace =TRUE),
Var3 = sample(10:100,12, replace =TRUE),
Var4 = sample(15:45,12, replace =TRUE),
Var5 = sample(50:200,12, replace =TRUE),
Var6 = sample(15:100,12, replace =TRUE),
Var7 = c(rep(0,3),rep(13,6),rep(0,3)),
Var8 = rep(5,12))
colnames(df_downloaded) <- c("Diversion.Date","360410059","360410060",
"360410209","361000655","361000656","Irrigation","Seep")
df_download # not run
#
# Diversion.Date 360410059 360410060 360410209 361000655 361000656 Irrigation Seep
# 1 2012-01-01 93 57 28 101 16 0 5
# 2 2012-02-01 102 68 19 124 98 0 5
# 3 2012-03-01 124 93 36 109 56 0 5
# 4 2012-04-01 94 96 23 54 87 13 5
# 5 2012-05-01 83 70 43 119 15 13 5
# 6 2012-06-01 78 63 45 195 15 13 5
# 7 2012-07-01 86 77 20 130 63 13 5
# 8 2012-08-01 118 29 27 118 57 13 5
# 9 2012-09-01 142 18 45 116 27 13 5
# 10 2012-10-01 74 68 34 182 79 0 5
# 11 2012-11-01 106 48 27 95 74 0 5
# 12 2012-12-01 91 41 20 179 55 0 5
Reference Table ("stationIDs")
stationIDs <- data.frame(ID = c("360410059", "360410060", "360410209", "361000655", "361000656"),
Names = c("RimView", "IPCO", "WMA.Ditch", "RV.Bypass", "LowerFalls"))
stationIDs # not run
#
# ID Names
# 1 360410059 RimView
# 2 360410060 IPCO
# 3 360410209 WMA.Ditch
# 4 361000655 RV.Bypass
# 5 361000656 LowerFalls
I can replace the column names in "df_downloaded" using individual statements. I show the first three iterations below.
After three iterations "RimValley", "IPCO", and "WMA.Ditch" have replaced their respective gauge ID numbers.
names(df_downloaded) <- gsub(stationIDs$ID[1],stationIDs$Name[1],names(df_downloaded))
# head(df_downloaded)
# Diversion.Date RimView 360410060 360410209 361000655 361000656 Irrigation Seep
# 1 2012-01-01 93 57 28 101 16 0 5
# 2 2012-02-01 102 68 19 124 98 0 5
# 3 2012-03-01 124 93 36 109 56 0 5
# 4 2012-04-01 94 96 23 54 87 13 5
# 5 2012-05-01 83 70 43 119 15 13 5
# 6 2012-06-01 78 63 45 195 15 13 5
names(df_downloaded) <- gsub(stationIDs$ID[2],stationIDs$Name[2],names(df_downloaded))
# head(df_downloaded)
# Diversion.Date RimView IPCO 360410209 361000655 361000656 Irrigation Seep
# 1 2012-01-01 93 57 28 101 16 0 5
# 2 2012-02-01 102 68 19 124 98 0 5
# 3 2012-03-01 124 93 36 109 56 0 5
# 4 2012-04-01 94 96 23 54 87 13 5
# 5 2012-05-01 83 70 43 119 15 13 5
# 6 2012-06-01 78 63 45 195 15 13 5
names(df_downloaded) <- gsub(stationIDs$ID[3],stationIDs$Name[3],names(df_downloaded))
# head(df_downloaded)
# Diversion.Date RimView IPCO WMA.Ditch 361000655 361000656 Irrigation Seep
# 1 2012-01-01 93 57 28 101 16 0 5
# 2 2012-02-01 102 68 19 124 98 0 5
# 3 2012-03-01 124 93 36 109 56 0 5
# 4 2012-04-01 94 96 23 54 87 13 5
# 5 2012-05-01 83 70 43 119 15 13 5
# 6 2012-06-01 78 63 45 195 15 13 5
If I try to do the renaming using a for loop, I end up with NAs for column names.
for(i in seq_along(names(df_downloaded))){
names(df_downloaded) <- gsub(stationIDs$ID[i],stationIDs$Name[i],names(df_downloaded))
}
# head(df_downloaded)
# NA NA NA NA NA NA NA NA
# 1 2012-01-01 93 57 28 101 16 0 5
# 2 2012-02-01 102 68 19 124 98 0 5
# 3 2012-03-01 124 93 36 109 56 0 5
# 4 2012-04-01 94 96 23 54 87 13 5
# 5 2012-05-01 83 70 43 119 15 13 5
# 6 2012-06-01 78 63 45 195 15 13 5
I really want to be able to change the names with a for loop or something similar, because because the number of stations that I download data from changes depending on the years that I am analyzing.
Thanks for taking time to look at my question.
We can use match
#Convert factor columns to character
stationIDs[] <- lapply(stationIDs, as.character)
#Match names of df_downloaded with stationIDs$ID
inds <- match(names(df_downloaded), stationIDs$ID)
#Replace the matched name with corresponding Names from stationIDs
names(df_downloaded)[which(!is.na(inds))] <- stationIDs$Names[inds[!is.na(inds)]]
df_downloaded
# Diversion.Date RimView IPCO WMA.Ditch RV.Bypass LowerFalls Irrigation Seep
#1 2012-01-01 142 14 41 200 79 0 5
#2 2012-02-01 97 100 35 176 22 0 5
#3 2012-03-01 85 59 26 88 71 0 5
#4 2012-04-01 68 49 34 63 15 13 5
#5 2012-05-01 62 58 44 87 16 13 5
#6 2012-06-01 70 59 33 145 87 13 5
#7 2012-07-01 112 65 25 52 64 13 5
#8 2012-08-01 75 12 27 103 19 13 5
#9 2012-09-01 73 65 36 172 68 13 5
#10 2012-10-01 87 35 27 146 42 0 5
#11 2012-11-01 122 17 33 183 32 0 5
#12 2012-12-01 108 65 15 120 99 0 5