similar to: Multiple Merge

Displaying 20 results from an estimated 10000 matches similar to: "Multiple Merge"

2009 Jan 21
3
merging several dataframes from a list
Hi there, I have a list of dataframes (generated by reading multiple files) and all dataframes are comparable in dimension and column names. They also have a common column, which, I'd like to use for merging. To give a simple example of what I have: df1 <- data.frame(c(LETTERS[1:5]), c(2,6,3,1,9)) names(df1) <- c("pos", "data") df3 <- df2 <- df1 df2$data
2008 Feb 19
2
Looping through a list of objects & do something...
Hey Folks, Could somebody show me how to loop through a list of dataframes? I want to be able to generically access their elements and do something with them. For instance, instead of this: df1<- data.frame(x=(1:5),y=(1:5)); df2<- data.frame(x=(1:5),y=(1:5)); df3<- data.frame(x=(1:5),y=(1:5)); plot(df1$x,df1$y); plot(df2$x,df2$y); plot(df3$x,df3$y); I would like to do something like:
2010 Jan 22
2
Question on Merge/Lookup
I need to merge three datasets and don't know how. If I were using SQL, I would use df3, look up the characteristics of each date in df1 and the value for each observation in df2. df1 - unique list of Dates and characteristics of those dates Date, YYYYMM, YYYYWW, DOW df2 - the raw data Date, Place, Value df3 - all posibile combinations of Date + Place (via
2012 Jun 03
2
merging single column from different dataframe
Hi all, probably really simple to solve, but having no background in programming I haven't been able to figure this out: I have two dataframes like df1 <- data.frame(names1=c('aa','ab', 'ac', 'ad'), var1=c(1,5,7,12)) df2 <- data.frame(names2=c('aa', 'ab', 'ac', 'ad', 'ae'), var2=c(3,6,9,12,15)) Now I want merge
2011 Jun 06
1
Merge two columns of a data frame
I have the following data: prefix <- c("cheap", "budget") roots <- c("car insurance", "auto insurance") suffix <- c("quote", "quotes") prefix2 <- c("cheap", "budget") roots2 <- c("car insurance", "auto insurance") roots3 <- c("car insurance", "auto
2011 Aug 18
2
Best way/practice to create a new data frame from two given ones with last column computed from the two data frames?
Dear expeRts, What is the best approach to create a third data frame from two given ones, when the new/third data frame has last column computed from the last columns of the two given data frames? ## Okay, sounds complicated, so here is an example. Assume we have the two data frames: df1 <- data.frame(Year=rep(2001:2010, each=2), Group=c("Group 1","Group 2"), Value=1:20)
2009 Oct 07
1
merging dataframes with an unequal number of variables
Hallo Everyone I have the kind of problem that one should never have because one must always plan well and communicate with your team. But now I haven't so here is my problem. I have data coming in on a daily basis from surveys in 10 towns. The questionnaire has 62 variables but some of the regions have used older versions of the questionnaire that have a few variables less. I want to combine
2010 Dec 16
2
Compare two dataframes
Hello, I have two dataframes DF1 and DF2 that should be identical but are not (DF1 has some rows that aren't in DF2, and vice versa). I would like to produce a new dataframe DF3 containing rows in DF1 that aren't in DF2 (and similarly DF4 would contain rows in DF2 that aren't in DF1). I have a solution for this problem (see self contained example below) but it's awkward and
2008 Mar 03
3
looping through data frames in a workspace
All, I have a workspace containing only data frame objects. I would like to loop though each one and clean-up text columns in them. How can I have R loop through the list? I have tried to find an answer in R help but the closest solution I can find is to make a static list of data frames, as illustrated in this recent post: ---------begin post On Tuesday 19 February 2008 (19:51:15), TLowe wrote:
2009 Feb 19
3
Multiple merge, better solution?
Hello, My problem is that I would like to merge multiple files with a common column but merge accepts only two data.frames to merge. In the real situation, I have 26 different data.frames with a common column. I can of course use merge many times (see below) but what would be more sophisticated solution? For loop? Any ideas? DF1 <- data.frame(var1 = letters[1:5], a = rnorm(5)) DF2 <-
2011 Aug 29
2
splitting into multiple dataframes and then create a loop to work
Dear All Sorry for this simple question, I could not solve it by spending days. My data looks like this: # data set.seed(1234) clvar <- c( rep(1, 10), rep(2, 10), rep(3, 10), rep(4, 10)) # I have 100 level for this factor var; yvar <- rnorm(40, 10,6); var1 <- rnorm(40, 10,4); var2 <- rnorm(40, 10,4); var3 <- rnorm(40, 5, 2); var4 <- rnorm(40, 10, 3); var5 <- rnorm(40, 15,
2013 Apr 02
2
Create a vector without using an external 'if statement'
Dear R-users, suppose I have three dataframes like these df1: mydate min_temp 31032013 12 01042013 8 02042013 -999 df2: mydate min_temp 31032013 10 01042013 11 02042013 14 df3: mydate min_temp 31032013 4 01042013 3 02042013 5 where -999 means that the temperature data is not available (at the moment I cannot change it to NA because I am not the db administrator); suppose also that oggi is
2012 Jul 11
1
sapply question
Why does this sapply code change df3 but not df1? Thanks df1 <- read.table(text=" cola colb colc cold cole 1 NA 5 9 NA 17 2 NA 6 NA 14 NA 3 3 NA 11 15 19 4 4 8 12 NA 20 ", header=TRUE) df2 <-df1*2 df1 df2 df3 <-sapply(names(df1),function(x) {df1[[x]]<- df2[[x]]}) df1 df3 [[alternative HTML version deleted]]
2011 Apr 30
3
indexing into a data.frame using another data.frame that also contains values for replacement
Hello all, I have a quandry I have been scratching my head about for a while. I've searched the manual and the web and have not been able to find an acceptable result, so I am hoping for some help. I have two data frames and I want to index into the first using the second, and replace the specific values I have indexed with more values from the second data.frame. I can do this
2003 Sep 04
1
error in lm.fit
Hello R user, I have several data frames with >100 columns and I did a linear regression over time of each column df1.lm <- lapply(df1, function(x) lm(x~year)$coeff[2]) that worked fine and I get slope of each column oder time - until I divided df1 by df2 df3 <- df1/df2 > df3.lm <- lapply(df3, function(x) lm(x~year)$coeff[2]) Error in lm.fit(x, y, offset = offset, ...) :
2011 Mar 18
1
Problem with Slope.test function
Hi all, I need to test the significnce of difference between slopes of two regression lines and regression line with theoretical line. I try to use Slope.test function from emu package, but an error occured... library(emu) d1<-data.frame(P1=c(1,2,3,5,7,8,9,13,14,15), P2=c(1,2,5,8,11,13,15,15,18,24), R=c(2,7,8,9,16,21,27,31,33,36)) # First data set m1<-lm(R~P1+P2+P1*P2,data=d1) # Regr.
2011 Oct 03
2
Merge two data frames and find common values and non-matching values
Hi, I am trying to find a function to match two data frames of different lengths for one field only. So, for example, df1 is: Name Position location francesca A 75 cristina B 36 And df2 is: location Country 75 UK 56 Austria And I would like to match on "Location" and the output to be something like: Name Position Location Match francesca A 75 1 cristina B 36 0 I have tried with
2004 Mar 09
5
Adding data.frames together
I have a series of data frames that are identical structurally, i.e. - made with the same code, but I need to add them together so that they become one, longer, data frame, i.e. - each of the slot vectors are increased in length by the length of the added data frame vectors. So if I have df1 with a slot A so that length(df1$A) = 100 and I have df2 with a slot A so that length(df2$A)=200 then I
2005 Oct 20
1
Windows 2000 crash while using rbind (PR#8225)
Windows 2000 reports that "Rgui.exe has generated errors and will be = closed by Windows. You will need to restart the program." when using = rbind.=20 df1 <- data.frame(cbind(x=3D1, y=3D1:1000), fac=3Dsample(LETTERS[1:3], = 1000, repl=3DTRUE)) df2 <- data.frame(cbind(x=3D1, y=3D1:10), fac=3Dsample(LETTERS[4:6], = 10, repl=3DTRUE)) df3 <- data.frame(cbind(x=3D1,
2006 Aug 13
2
How to order or sort a data.frame
I have a dataframe where I would like to order first by variable, year, and then within that variable by month. So far the only way that I have seen to do this is to order by year and then subset year and sort by month and then do an rbind to get things back together. Is this the right approach? Example: us.state <-rep("California", 23)