similar to: select columns from dataframe

Displaying 20 results from an estimated 5000 matches similar to: "select columns from dataframe"

2010 Jul 09
2
select columns from vector of column names
Hi I want to extract columns from a data frame using a vector with the desired column names. This short example uses the select argument in the subset function to accomplish what I am trying to do. Is there a better solution? #names of desired columns colnames <- c("col1","col3") #my data data <-
2008 Sep 12
2
Finding a vector position using names rather than values
Dear R gurus, I have been struggling with this for a while and thought you might be able to give me some guidance. I have a data frame, on which I apply a row function. The result looks to me like a vector that retains the old row names. I then sort the vector and subsequently need to be able to identify the rank of certain values by searching for their row names. See this mock example: >
2010 Jul 26
4
using string variable as order() function argument
Hello, In my script I would like to use a loop, which sorts the dataframe according to different columns, pointed by the string variable. id col1 col2 col3 1 10 0 4 8 2 11 1 2 2 3 12 0 8 3 4 13 0 5 5 Usually the order() function can be used like this: sorted = mytable**[order(column3) , ] which results in properly sorted table: **
2006 Jun 09
3
sqlSave() and rownames=TRUE makes my Rgui crash
Hello, I created a table in MySQL with this command CREATE TABLE example (pk INT NOT NULL AUTO_INCREMENT,PRIMARY KEY(pk), id VARCHAR(30),col1 VARCHAR(30),col2 VARCHAR(30)) ### In R, I can connect to this table: library(DBI) library(RODBC) chan <- odbcConnect("MySQL51", uid="root", pwd="xxx") first <- sqlQuery(chan, "select * from example")
2006 Mar 16
3
Did I use "step" function correctly? (Is R's step() function reliable?)
Hi all, I put up an exhaustive model to use R's "step" function: ------------------------ mygam=gam(col1 ~ 1 + col2 + col3 + col4 + col2 ^ 2 + col3 ^ 2 + col4 ^ 2 + col2 ^ 3 + col3 ^ 3 + col4 ^ 3 + s(col2, 1) + s(col3, 1) + s(col4, 1) + s(col2, 2) + s(col3, 2) + s(col4, 2) + s(col2, 3) + s(col3, 3) + s(col4, 3) + s(col2, 4) + s(col3, 4) + s(col4, 4) + s(col2, 5) + s(col3,
2011 Jul 08
1
Referencing a vector of data labels in ggplot function
Hi, I really feel I've looked everywhere, although I know this can't be a hard problem. I'd like to be able to call the graph below as a function, but I can't get the function to recognize variables beyond 'dframe'. I've read through many papers on writing functions in R, but I can't get this to work. data <- data.frame('date' = as.Date(rep(c(15101,
2018 Feb 25
2
include
HI Jim and all, I want to put one more condition. Include col2 and col3 if they are not in col1. Here is the data mydat <- read.table(textConnection("Col1 Col2 col3 K2 X1 NA Z1 K1 K2 Z2 NA NA Z3 X1 NA Z4 Y1 W1"),header = TRUE,stringsAsFactors=FALSE) The desired out put would be Col1 Col2 col3 1 X1 0 0 2 K1 0 0 3 Y1 0 0 4 W1 0 0 6 K2 X1
2018 Feb 25
0
include
Hi Val, My fault - I assumed that the NA would be first in the result produced by "unique": mydat <- read.table(textConnection("Col1 Col2 col3 Z1 K1 K2 Z2 NA NA Z3 X1 NA Z4 Y1 W1"),header = TRUE,stringsAsFactors=FALSE) val23<-unique(unlist(mydat[,c("Col2","col3")])) napos<-which(is.na(val23)) preval<-data.frame(Col1=val23[-napos],
2018 Feb 25
0
include
Jim has been exceedingly patient (and may well continue to be so), but this smells like "failure to launch". At what point will you start showing your (failed) attempts at solving your own problems so we can help you work on your specific weaknesses and become self-sufficient? -- Sent from my phone. Please excuse my brevity. On February 25, 2018 7:55:55 AM PST, Val <valkremk at
2018 Feb 25
0
include
hi Val, Your problem seems to be that the data are read in as a factor. The simplest way I can think of to get around this is: mydat <- read.table(textConnection("Col1 Col2 col3 Z1 K1 K2 Z2 NA NA Z3 X1 NA Z4 Y1 W1"),header = TRUE,stringsAsFactors=FALSE) preval<-data.frame(Col1=unique(unlist(mydat[,c("Col2","col3")]))[-1], Col2=NA,col3=NA) rbind(preval,mydat)
2008 Mar 16
2
How to loop through all the columns in dataframe
Hi: Can anyone advice me on how to loop and perform a calculation through all the columns. here's my data xd<- c(2.2024,2.4216,1.4672,1.4817,1.4957,1.4431,1.5676) pd<- c(0.017046,0.018504,0.012157,0.012253,0.012348,0.011997,0.012825) td<- c(160524,163565,143973,111956,89677,95269,81558) mydf<-data.frame(xd,pd,td) trans<-t(mydf) trans I have these values that I need to
2018 Feb 25
2
include
Sorry , I hit the send key accidentally here is my complete message. Thank you Jim and all, I got it. I have one more question on the original question What does this "[-1] " do? preval<-data.frame(Col1=unique(unlist(mydat[,c("Col2","col3")]))[-1], Col2=NA,col3=NA) mydat <- read.table(textConnection("Col1 Col2 col3 Z1 K1 K2 Z2
2018 Feb 25
3
include
Thank you Jim, I read the data as you suggested but I could not find K1 in col1. rbind(preval,mydat) Col1 Col2 col3 1 <NA> <NA> <NA> 2 X1 <NA> <NA> 3 Y1 <NA> <NA> 4 K2 <NA> <NA> 5 W1 <NA> <NA> 6 Z1 K1 K2 7 Z2 <NA> <NA> 8 Z3 X1 <NA> 9 Z4 Y1 W1 On Sat, Feb 24, 2018 at 6:18 PM, Jim
2018 Feb 24
0
include
Thank you Jim and all, I got it. I have one more question on the original question What does this "[-1] " do? preval<-data.frame(Col1=unique(unlist(mydat[,c("Col2","col3")]))[-1], Col2=NA,col3=NA) mydat <- read.table(textConnection("Col1 Col2 col3 Z1 K1 K2 Z2 NA NA Z3 X1 NA Z4 Y1 W1"),header = TRUE)
2013 Jan 11
3
split & rbind (cast) dataframe
Hi, I would like to split dataframe based on one colum and want to connect the two dataframes by rows (like rbind). Here a small example: # The orgininal dataframe df1 <- data.frame(col1 = c("A","A","B","B"),col2 = c(1:4), col3 = c(1:4)) # The datafame how it could look like df2 <- data.frame(A.col2 = c(1,2), A.col3 = c(1,2), B.col2 = c(3,4), B.col3
2006 Dec 14
5
Better way to change the name of a column in a dataframe?
Hello R users -- If I have a dataframe such as the following, named "frame" with the columns intended to be named col1 through col6, > frame col1 col2 cmlo3 col4 col5 col6 [1,] 3 10 2 6 5 7 [2,] 6 8 4 10 7 1 [3,] 7 5 1 3 1 8 [4,] 10 6 5 4 9 2 and I want to correct or otherwise change the
2010 May 11
1
create a data.frame for aov
Hi R-experts, I try to find a way to transfer a matrix to a data.frame that is used as input of aov. can you give me advice for that? >mdat <- matrix(c(1,2,3, 11,12,13), nrow = 2, ncol=3, byrow=TRUE, dimnames = list(c("row1", "row2"), c("Col1", "Col2", "Col3"))) >mdat      Col1 Col2 Col3 row1    1    2    3 row2   11   12   13 ===>
2004 Aug 18
1
header line generated write.table
I want to write following data frame into a CSV file: Col1 Col2 Col3 Row1 1 1 1 Row2 2 2 2 where Row1, Row2 are the row names and Col1, Col2, Col3 are the column names. The correct CSV file should be: ,"Col1","Col2","Col3" Row1,1,1,1 Row2,2,2,2 However, the one generated by R using write.table(x, file="xyz.csv",
2017 Jun 21
4
selecting dataframe columns based on substring of col name(s)
Suppose I have the following sort of dataframe, where each column name has a common structure: prefix, followed by a number (for this example, col1, col2, col3 and col4): d = data.frame( col1=runif(10), col2=runif(10), col3=runif(10),col4=runif(10)) What I haven't been able to suss out is how to efficiently 'extract/manipulate/play with' columns from the data frame, making use
2010 Oct 11
2
Split rows depending on time frame
Hi, I have the following data frame, where col2 is a startdate and col3 an enddate COL1 COL2 COL3 A 40462 40482 B 40462 40478 The above timeframe of 3 weeks I would like to splits it in weeks like this COL1 COL2 COL3 COL4 A 40462 40468 1 A 40469 40475 1 A 40476 40482 1 B