How do i use a loop to delete columns in a data frame?
My code:
SMI_Mly$V1 <- NULL
SMI_Mly$V2 <- NULL
SMI_Mly$V3 <- NULL
SMI_Mly$V4 <- NULL
...
SMI_Mly$V10 <- NULL
I am sure there is a better and shorter way to delete all these columns from the dataframe. Maybe by using a loop? Can someone please show me how to do it?
r loops dataframe
edited Nov 28 '18 at 13:34
markus
14.8k11336
asked Nov 26 '18 at 11:28
TheBeginnerTheBeginner
62
add a comment |
My code:
SMI_Mly$V1 <- NULL
SMI_Mly$V2 <- NULL
SMI_Mly$V3 <- NULL
SMI_Mly$V4 <- NULL
...
SMI_Mly$V10 <- NULL
I am sure there is a better and shorter way to delete all these columns from the dataframe. Maybe by using a loop? Can someone please show me how to do it?
r loops dataframe
edited Nov 28 '18 at 13:34
markus
14.8k11336
asked Nov 26 '18 at 11:28
TheBeginnerTheBeginner
62
SMI_Mly[paste0("V", c(1:10))] <- NULL, please also consider to accept Tim's answer if it solved your problem.
– markus
Nov 28 '18 at 13:36
add a comment |
My code:
SMI_Mly$V1 <- NULL
SMI_Mly$V2 <- NULL
SMI_Mly$V3 <- NULL
SMI_Mly$V4 <- NULL
...
SMI_Mly$V10 <- NULL
I am sure there is a better and shorter way to delete all these columns from the dataframe. Maybe by using a loop? Can someone please show me how to do it?
r loops dataframe
edited Nov 28 '18 at 13:34
markus
14.8k11336
asked Nov 26 '18 at 11:28
TheBeginnerTheBeginner
62
My code:
SMI_Mly$V1 <- NULL
SMI_Mly$V2 <- NULL
SMI_Mly$V3 <- NULL
SMI_Mly$V4 <- NULL
...
SMI_Mly$V10 <- NULL
I am sure there is a better and shorter way to delete all these columns from the dataframe. Maybe by using a loop? Can someone please show me how to do it?
r loops dataframe
r loops dataframe
edited Nov 28 '18 at 13:34
markus
14.8k11336
asked Nov 26 '18 at 11:28
TheBeginnerTheBeginner
62
edited Nov 28 '18 at 13:34
markus
14.8k11336
asked Nov 26 '18 at 11:28
TheBeginnerTheBeginner
62
edited Nov 28 '18 at 13:34
markus
14.8k11336
edited Nov 28 '18 at 13:34
markus
14.8k11336
edited Nov 28 '18 at 13:34
markus
14.8k11336
14.8k11336
asked Nov 26 '18 at 11:28
TheBeginnerTheBeginner
62
asked Nov 26 '18 at 11:28
TheBeginnerTheBeginner
62
asked Nov 26 '18 at 11:28
TheBeginnerTheBeginner
62
62
SMI_Mly[paste0("V", c(1:10))] <- NULL, please also consider to accept Tim's answer if it solved your problem.
– markus
Nov 28 '18 at 13:36
add a comment |
SMI_Mly[paste0("V", c(1:10))] <- NULL, please also consider to accept Tim's answer if it solved your problem.
– markus
Nov 28 '18 at 13:36
SMI_Mly[paste0("V", c(1:10))] <- NULL, please also consider to accept Tim's answer if it solved your problem.– markus
Nov 28 '18 at 13:36
SMI_Mly[paste0("V", c(1:10))] <- NULL, please also consider to accept Tim's answer if it solved your problem.– markus
Nov 28 '18 at 13:36
add a comment |
1 Answer
1
active
oldest
votes
You may use an appropriate subset here:
cols <- paste0("V", c(1:10))
indices <- sapply(cols, function(x) { grep(x, names(df)) })
SMI_Mly[, -indices]
The above call to sapply generates the positional indices of the columns V1 to V10 which you wish to exclude from your data frame. Then, we may use subset notation to exclude those columns.
answered Nov 26 '18 at 11:31
Tim BiegeleisenTim Biegeleisen
236k13100160
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
You may use an appropriate subset here:
cols <- paste0("V", c(1:10))
indices <- sapply(cols, function(x) { grep(x, names(df)) })
SMI_Mly[, -indices]
The above call to sapply generates the positional indices of the columns V1 to V10 which you wish to exclude from your data frame. Then, we may use subset notation to exclude those columns.
answered Nov 26 '18 at 11:31
Tim BiegeleisenTim Biegeleisen
236k13100160
add a comment |
You may use an appropriate subset here:
cols <- paste0("V", c(1:10))
indices <- sapply(cols, function(x) { grep(x, names(df)) })
SMI_Mly[, -indices]
The above call to sapply generates the positional indices of the columns V1 to V10 which you wish to exclude from your data frame. Then, we may use subset notation to exclude those columns.
answered Nov 26 '18 at 11:31
Tim BiegeleisenTim Biegeleisen
236k13100160
add a comment |
You may use an appropriate subset here:
cols <- paste0("V", c(1:10))
indices <- sapply(cols, function(x) { grep(x, names(df)) })
SMI_Mly[, -indices]
The above call to sapply generates the positional indices of the columns V1 to V10 which you wish to exclude from your data frame. Then, we may use subset notation to exclude those columns.
answered Nov 26 '18 at 11:31
Tim BiegeleisenTim Biegeleisen
236k13100160
You may use an appropriate subset here:
cols <- paste0("V", c(1:10))
indices <- sapply(cols, function(x) { grep(x, names(df)) })
SMI_Mly[, -indices]
The above call to sapply generates the positional indices of the columns V1 to V10 which you wish to exclude from your data frame. Then, we may use subset notation to exclude those columns.
answered Nov 26 '18 at 11:31
Tim BiegeleisenTim Biegeleisen
236k13100160
edited Nov 26 '18 at 11:37
answered Nov 26 '18 at 11:31
Tim BiegeleisenTim Biegeleisen
236k13100160
answered Nov 26 '18 at 11:31
Tim BiegeleisenTim Biegeleisen
236k13100160
answered Nov 26 '18 at 11:31
Tim BiegeleisenTim Biegeleisen
236k13100160
236k13100160
add a comment |
add a comment |
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SMI_Mly[paste0("V", c(1:10))] <- NULL, please also consider to accept Tim's answer if it solved your problem.– markus
Nov 28 '18 at 13:36