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removing columns with negative indexing

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chuck.01

removing columns with negative indexing

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Hi,
I am trying to remove columns from the example data "a" given below.
Shouldn't the line below the data work? Please let me know what I am doing wrong.

a <- dput(new2[1:5,c(6:10)])
structure(list(Last.Name.x = c("Bell", "Procell", "Denney", "Woods",
"Bates"), First.Name.x = c("Amanda", "Jordan", "Thomas", "David",
"Charles"), Lab.01.Bonus..2000589. = c(2L, 2L, 0L, 0L, 0L), Lab.01.Entrance..1999102. = c(10L,
8L, 0L, 0L, 0L), Lab.02.Entrance..1999133. = c(10L, 10L, 6L,
0L, 0L)), .Names = c("Last.Name.x", "First.Name.x", "Lab.01.Bonus..2000589.",
"Lab.01.Entrance..1999102.", "Lab.02.Entrance..1999133."), row.names = c(NA,
5L), class = "data.frame")

# why doesn't this work?
a[, -c("First.Name.x", "Last.Name.x")]

Thanks ahead of time.

arun kirshna

Re: removing columns with negative indexing

This post has NOT been accepted by the mailing list yet.

This post was updated on .

Hi,
Either use:
a[!grepl("First.Name.x|Last.Name.x",colnames(a))]
#or
a[,!(colnames(a)=="First.Name.x"|colnames(a)=="Last.Name.x")]
#or
a[,!(colnames(a)%in% c("First.Name.x","Last.Name.x"))]
# Lab.01.Bonus..2000589. Lab.01.Entrance..1999102. Lab.02.Entrance..1999133.
#1 2 10 10
#2 2 8 10
#3 0 0 6
#4 0 0 0
#5 0 0 0
#or
a[,-match(c("Last.Name.x","First.Name.x"),colnames(a))]
#or
a[,-which(colnames(a)%in% c("First.Name.x","Last.Name.x"))]
# Lab.01.Bonus..2000589. Lab.01.Entrance..1999102. Lab.02.Entrance..1999133.
#1 2 10 10
#2 2 8 10
#3 0 0 6
#4 0 0 0
#5 0 0 0

A.K.