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Joel Fürstenberg-Hägg

2012-Feb-17 13:26 UTC

[R] How to change the order of columns in a data frame?

Dear all,
 
I have a data frame in which the columns need to be ordered. The first column X
is at the right position, but the remaining columns X1-Xn should be ordered like
this: X1, X2, X3 etc instead of like below.
 > colnames(pos1) [1] "X"   "X1"  "X10" "X11"
"X12" "X13" "X14" "X15" "X16"
"X17" "X18" "X19" "X2"  "X20"
"X3"  "X4"  "X5"  "X6"  "X7" 
"X8"  "X9"
 > pos1[1:5,1:5]      X       X1       X10       X11       X12
1 100.5 7949.469 18509.064  8484.969 17401.056
2 101.5 3080.058  7794.691  3211.323  8211.058
3 102.5 1854.347  4347.571  1783.846  4827.338
4 103.5 2064.441  8421.746  2012.536  8363.785
5 104.5 9650.402 26637.926 10730.647 27053.421
 
I am trying to first change the first column name to something without an X and
save as a vector. I would then remove the X from each position use the vector
for renaming the columns. Then the column 2-n could be ordered, I hope...

colnames(pos)[1] <- "Mass"
columnNames <- colnames(pos)
 
Does any of you have an idea how to do this, or perhaps there is a smoother
solution?
Would it be easier to solve it if the contents of the first column were
extracted and used as row names instead?
 
Best regards,
 
Joel

	[[alternative HTML version deleted]]

Sarah Goslee

2012-Feb-17 13:36 UTC

head link

[R] How to change the order of columns in a data frame?

> fakedata <- data.frame(A=c(0,0,0), X2=c(2,2,2), X1=c(1,1,1),
X3=c(3,3,3))
> fakedata  A X2 X1 X3
1 0  2  1  3
2 0  2  1  3
3 0  2  1  3> pos <- colnames(fakedata)[2:ncol(fakedata)]
> pos <- c(1, 1+as.numeric(gsub("X", "", pos)))
> fakedata[,  pos]  A X1 X2 X3
1 0  1  2  3
2 0  1  2  3
3 0  1  2  3>
Sarah

2012/2/17 Joel F?rstenberg-H?gg <joelf at
life.ku.dk>:> Dear all,
>
> I have a data frame in which the columns need to be ordered. The first
column X is at the right position, but the remaining columns X1-Xn should be
ordered like this: X1, X2, X3 etc instead of like below.
>
>> colnames(pos1)
> ?[1] "X" ? "X1" ?"X10" "X11"
"X12" "X13" "X14" "X15" "X16"
"X17" "X18" "X19" "X2" ?"X20"
"X3" ?"X4" ?"X5" ?"X6" ?"X7"
?"X8" ?"X9"
>
>> pos1[1:5,1:5]
> ? ? ?X ? ? ? X1 ? ? ? X10 ? ? ? X11 ? ? ? X12
> 1 100.5 7949.469 18509.064 ?8484.969 17401.056
> 2 101.5 3080.058 ?7794.691 ?3211.323 ?8211.058
> 3 102.5 1854.347 ?4347.571 ?1783.846 ?4827.338
> 4 103.5 2064.441 ?8421.746 ?2012.536 ?8363.785
> 5 104.5 9650.402 26637.926 10730.647 27053.421
>
> I am trying to first change the first column name to something without an X
and save as a vector. I would then remove the X from each position use the
vector for renaming the columns. Then the column 2-n could be ordered, I hope...
>
> colnames(pos)[1] <- "Mass"
> columnNames <- colnames(pos)
>
> Does any of you have an idea how to do this, or perhaps there is a smoother
solution?
> Would it be easier to solve it if the contents of the first column were
extracted and used as row names instead?
>
> Best regards,
>
> Joel
>

-- 
Sarah Goslee
http://www.functionaldiversity.org

Alfredo Alessandrini

2012-Feb-17 13:40 UTC

head link

[R] How to change the order of columns in a data frame?

Hi Joel,

to replace the colnames:

colnames(dataframe <- )gsub("X","",colnames(dataframe))

to order by colnames:

dataframe <- dataframe[,colnames(dataframe)]



Alfredo


2012/2/17 Joel Fürstenberg-Hägg <joelf@life.ku.dk>
> Dear all,
>
> I have a data frame in which the columns need to be ordered. The first
> column X is at the right position, but the remaining columns X1-Xn should
> be ordered like this: X1, X2, X3 etc instead of like below.
>
> > colnames(pos1)
>  [1] "X"   "X1"  "X10" "X11"
"X12" "X13" "X14" "X15" "X16"
"X17" "X18"
> "X19" "X2"  "X20" "X3" 
"X4"  "X5"  "X6"  "X7"  "X8" 
"X9"
>
> > pos1[1:5,1:5]
>      X       X1       X10       X11       X12
> 1 100.5 7949.469 18509.064  8484.969 17401.056
> 2 101.5 3080.058  7794.691  3211.323  8211.058
> 3 102.5 1854.347  4347.571  1783.846  4827.338
> 4 103.5 2064.441  8421.746  2012.536  8363.785
> 5 104.5 9650.402 26637.926 10730.647 27053.421
>
> I am trying to first change the first column name to something without an
> X and save as a vector. I would then remove the X from each position use
> the vector for renaming the columns. Then the column 2-n could be ordered,
> I hope...
>
> colnames(pos)[1] <- "Mass"
> columnNames <- colnames(pos)
>
> Does any of you have an idea how to do this, or perhaps there is a
> smoother solution?
> Would it be easier to solve it if the contents of the first column were
> extracted and used as row names instead?
>
> Best regards,
>
> Joel
>
>        [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
	[[alternative HTML version deleted]]

jim holtman

2012-Feb-17 13:44 UTC

head link

[R] How to change the order of columns in a data frame?

pos2 <- pos1[, c("X", "X1", "X2",
"X3", "X4", "X5", "X6", "X7",
"X8",
"X9", "X10", "X11", "X12",
      "X13", "X14", "X15", "X16",
"X17", "X18", "X19", "X20")]


2012/2/17 Joel F?rstenberg-H?gg <joelf at
life.ku.dk>:> Dear all,
>
> I have a data frame in which the columns need to be ordered. The first
column X is at the right position, but the remaining columns X1-Xn should be
ordered like this: X1, X2, X3 etc instead of like below.
>
>> colnames(pos1)
> ?[1] "X" ? "X1" ?"X10" "X11"
"X12" "X13" "X14" "X15" "X16"
"X17" "X18" "X19" "X2" ?"X20"
"X3" ?"X4" ?"X5" ?"X6" ?"X7"
?"X8" ?"X9"
>
>> pos1[1:5,1:5]
> ? ? ?X ? ? ? X1 ? ? ? X10 ? ? ? X11 ? ? ? X12
> 1 100.5 7949.469 18509.064 ?8484.969 17401.056
> 2 101.5 3080.058 ?7794.691 ?3211.323 ?8211.058
> 3 102.5 1854.347 ?4347.571 ?1783.846 ?4827.338
> 4 103.5 2064.441 ?8421.746 ?2012.536 ?8363.785
> 5 104.5 9650.402 26637.926 10730.647 27053.421
>
> I am trying to first change the first column name to something without an X
and save as a vector. I would then remove the X from each position use the
vector for renaming the columns. Then the column 2-n could be ordered, I hope...
>
> colnames(pos)[1] <- "Mass"
> columnNames <- colnames(pos)
>
> Does any of you have an idea how to do this, or perhaps there is a smoother
solution?
> Would it be easier to solve it if the contents of the first column were
extracted and used as row names instead?
>
> Best regards,
>
> Joel
>
> ? ? ? ?[[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.


-- 
Jim Holtman
Data Munger Guru

What is the problem that you are trying to solve?
Tell me what you want to do, not how you want to do it.

Petr Savicky

2012-Feb-17 13:46 UTC

head link

[R] How to change the order of columns in a data frame?

On Fri, Feb 17, 2012 at 02:26:52PM +0100, Joel F?rstenberg-H?gg
wrote:> Dear all,
>  
> I have a data frame in which the columns need to be ordered. The first
column X is at the right position, but the remaining columns X1-Xn should be
ordered like this: X1, X2, X3 etc instead of like below.
>  
> > colnames(pos1)
>  [1] "X"   "X1"  "X10" "X11"
"X12" "X13" "X14" "X15" "X16"
"X17" "X18" "X19" "X2"  "X20"
"X3"  "X4"  "X5"  "X6"  "X7" 
"X8"  "X9"
>  
> > pos1[1:5,1:5]
>       X       X1       X10       X11       X12
> 1 100.5 7949.469 18509.064  8484.969 17401.056
> 2 101.5 3080.058  7794.691  3211.323  8211.058
> 3 102.5 1854.347  4347.571  1783.846  4827.338
> 4 103.5 2064.441  8421.746  2012.536  8363.785
> 5 104.5 9650.402 26637.926 10730.647 27053.421
>  
> I am trying to first change the first column name to something without an X
and save as a vector. I would then remove the X from each position use the
vector for renaming the columns. Then the column 2-n could be ordered, I hope...
> 
> colnames(pos)[1] <- "Mass"
> columnNames <- colnames(pos)
Hi.

Try the following. For simplicity, i assume the first 
column to be X0, but this is not necessary. Example data

  a <- sort(paste("A", 0:19, sep=""))
  names(a) <- sort(paste("X", 0:19, sep=""))
  pos <- data.frame(rbind(a))
  pos

    X0 X1 X10 X11 X12 X13 X14 X15 X16 X17 X18 X19 X2 X3 X4 X5 X6 X7 X8 X9
  a A0 A1 A10 A11 A12 A13 A14 A15 A16 A17 A18 A19 A2 A3 A4 A5 A6 A7 A8 A9

The reordering:

  columnNames <- colnames(pos)
  ind <- as.integer(substr(columnNames, 2, nchar(columnNames)))
  pos[, order(ind)]

    X0 X1 X2 X3 X4 X5 X6 X7 X8 X9 X10 X11 X12 X13 X14 X15 X16 X17 X18 X19
  a A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 A10 A11 A12 A13 A14 A15 A16 A17 A18 A19

Hope this helps.

Petr Savicky.

Joel Fürstenberg-Hägg

2012-Feb-17 14:08 UTC

head link

[R] How to change the order of columns in a data frame?

@Alfredo
 
The X is removed, but the reordering does not work:
 > colnames(df)[1] <- "Mass"
> columnNames <- colnames(df)
> colnames(df) [1] "Mass" "X1"   "X10"  "X11" 
"X12"  "X13"  "X14"  "X15" 
"X16"
"X17"  "X18"  "X19"  "X2"  
"X20"  "X3"   "X4"   "X5"  
"X6"   "X7"
"X8"   "X9"  > 
> colnames(df) <- gsub("X","",colnames(df))
> colnames(df) [1] "Mass" "1"    "10"   "11"  
"12"   "13"   "14"   "15"  
"16"
"17"   "18"   "19"   "2"   
"20"   "3"    "4"    "5"   
"6"    "7"
"8"    "9">
> df <- df[,colnames(df)]
> colnames(df) [1] "Mass" "1"    "10"   "11"  
"12"   "13"   "14"   "15"  
"16"
"17"   "18"   "19"   "2"   
"20"   "3"    "4"    "5"   
"6"    "7"
"8"    "9" 
 
Best,
 
Joel
 >>> Alfredo Alessandrini <cavenebula@gmail.com> 17-02-2012 14:40
>>>Hi Joel,

to replace the colnames:

colnames(dataframe <- )gsub("X","",colnames(dataframe))

to order by colnames:

dataframe <- dataframe[,colnames(dataframe)]



Alfredo


2012/2/17 Joel Fürstenberg-Hägg <joelf@life.ku.dk>


Dear all,

I have a data frame in which the columns need to be ordered. The first
column X is at the right position, but the remaining columns X1-Xn
should be ordered like this: X1, X2, X3 etc instead of like below.
> colnames(pos1)[1] "X" "X1" "X10" "X11" "X12"
"X13" "X14" "X15" "X16" "X17"
"X18"
"X19" "X2" "X20" "X3" "X4"
"X5" "X6" "X7" "X8" "X9"
> pos1[1:5,1:5]X X1 X10 X11 X12
1 100.5 7949.469 18509.064 8484.969 17401.056
2 101.5 3080.058 7794.691 3211.323 8211.058
3 102.5 1854.347 4347.571 1783.846 4827.338
4 103.5 2064.441 8421.746 2012.536 8363.785
5 104.5 9650.402 26637.926 10730.647 27053.421

I am trying to first change the first column name to something without
an X and save as a vector. I would then remove the X from each position
use the vector for renaming the columns. Then the column 2-n could be
ordered, I hope...

colnames(pos)[1] <- "Mass"
columnNames <- colnames(pos)

Does any of you have an idea how to do this, or perhaps there is a
smoother solution?
Would it be easier to solve it if the contents of the first column were
extracted and used as row names instead?

Best regards,

Joel

[[alternative HTML version deleted]]

______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.



	[[alternative HTML version deleted]]

R help - Feb 2012 - How to change the order of columns in a data frame?

[R] How to change the order of columns in a data frame?

[R] How to change the order of columns in a data frame?

[R] How to change the order of columns in a data frame?

[R] How to change the order of columns in a data frame?

[R] How to change the order of columns in a data frame?

[R] How to change the order of columns in a data frame?