similar to: How use lapply over one column in a dataframe?

Hi, I have a question about reformatting data. It looks like it should be simple, but I've been working at it for awhile now and it's about time I ask for help. My data look like this: ITEM VALUE STEP item1 A first item2 C first item2 D second item1 A second item3 A first item3 B second item3 A third I just want to transform

Hi all, I am not a skillful R programmer and has I am handling with large dataframes (about 30000 x 300) I am in need of an efficient function. I have 4 dataframes with the same dimension. I need to generate other dataframe with the some dimension than the others where in each position it has the median value of the 4 values in the same position coming from the 4 dataframes. Grateful by your

I'm importing a lot of text tables of data (from Latent Gold) that includes hashes in some of the column names ("Cluster#1", "Cluster#2", etc.). Is there an easy way to strip the offending hashes out before pushing the text into a table or data frame? I thought I'd use gsub, e.g., but can't figure out how to read in a text file without reading it into a table or

Hi, I still have little ability to predict how these functions will treat the columns of data frames: > # Here's a data frame with a column "a" of integers, > # and a column "b" of characters: > df <- data.frame( + a = 1:2, + b = c("a","b") + ) > df a b 1 1 a 2 2 b > > # Except -- both columns are characters: >

Can anyone explain how best to go from a dataframe to a table (or better yet a new dataframe) of counts, where the row names in the new table (or dataframe) are the column names of the original df. start w/ DF1 = Pos1 Pos2 Pos3 .... oligo1 G C A oligo2 U U A oligo3 G C C oligo4 C G U oligo5 A A G ..... End with DF2 =

Hi, To set a simple an clear picture of what I'd like to do, here is an example. I would like to calculate mean of column A and B bucketed by factor in column X in a data.frame. lapply or aggregate operates on a single column. I found dapply function in some package which doesn't seem to exist any more. Is there anyway that I can accomplish something like this? Thank you so much in

I have a dataset of property transactions that includes the transaction ID (TranID), property ID (UnitID), and transaction date (TranDt). I need to create a data frame (or data table) that includes the previous transaction date, if one exists. This is an easy problem in SQL, where I just run a sub-query, but I'm trying to make R my one-stop-shopping program. ?The following code works on a

I have solved this problem once before but don't recall exactly how. Is there a url that shows how? What I want to do now is quite specific but my query is actually very general There are many functions in which one specifies several parameters and an output is generated. Well what happens if one wants to specify a range of parameters and have the output written to a data frame. To

Here is some data (dput output below) > myData id group 1 D599 A 2 002-0004 B 3 F01932 A 18 F16 B 19

Hi there, I have a problem about lapply, strsplit, and accessing list elements, which I don't understand or cannot solve: I have e.g. a character vector with three elements: x = c("349/077,349/074,349/100,349/117", "340/384.2,340/513,367/139,455/128,D13/168", "600/437,128/903,128/904") The task I want to perform, is to generate a list,

Dear all, I am trying to avoid a for loop here and wonder if the following is possible: I have a data.frame with 6 columns and i want to get a cross-correlogram (by using ccf) . Obivously ccf only accepts two columns at once and then returms a list. In fact, with a for loop i?d do the following for (i in 1:6) { x[[i]]=ccf(mydf[,i],mydf[,6]) } Is there any chance to the same with

Dear R developers, Reviewing my code, I have realized that about 80% of the time in the lapply I need to access the names of the objects inside the loop. In such cases I iterate over indexes or names: lapply(names(x), ... [i]), lapply(seq_along(x), ... x[[i]] ... names(x)[i] ), or for(i in seq_along(x)) ... which is rather inconvenient. How about an argument to lapply which would specify the

Hello, I try to transform a data frame like A B C 1 1 2,5 2 2 NA 3 1 1,0 4 1 56 5 2 23 6 1 NA 7 2 46 to the following dataframe, calculating the variance and median of the C-column, group by B, so the result will be: B C(median) D (var) 1 19,83

I am trying to export a dateframe created in R: > Duration_summary V1 2.5 % 97.5 % V4 2.5 % 97.5 % [1,] 1 0.46076018 1.128776 1.000000 0.5280828 0.9576338 [2,] 0 0.00000000 0.000000 1.000000 0.1741793 1.2352705 [3,] 1 0.46566719 1.313711 1.000000 0.7233312 1.4097987 [4,] 1 0.38866371 2.453226 0.976024 0.6377314 1.3493957 [5,] 1 0.08894066 1.036830

Hi, I have a Dataframe. A B C D 0.1 0.7 0.9 0.8 0.20 0.60 0.80 0.70 0.40 0.80 0.70 0.76 I need a resultant dataframe (A-B) (C-D) -0.6 0.1 -0.40 0.1 -0.40 -0.06 Any suggestion would be of a great help Thanks Ramya -- View this message in context: http://r.789695.n4.nabble.com/Finding-a-Diff-within-a-Dataframe-columns-tp3247943p3247943.html Sent from

Dear R-helpers, i have a question on how to vectorize this problem: i have a dataframe: tester <- data.frame(groups=c("A","A","B","B","C","C"), one=c(1,1,2,2,3,3), two=c(6,6,7,7,8,8)) # i split it into a list tester.L <- split(tester, tester$groups) # And want to keep only the first item in each: lapply(tester.L, function(x) x

Hi , Dataframe Df contains more than 30 no of records.but I want only first 30 rows of data. How can I retrieve it. Thanks K.Ravichandra [[alternative HTML version deleted]]

dear all, I have two dataframes dataframe1 ID a b c dataframe2 ID value a;W 100 X;c 200 Y;Z 300 I wanted to match the IDs from the two dataframes and record the values into a new column of dataframe1 at the corresponding rows. This is what I expect: dataframe1 ID value a 100 b c 200 I tried doing it like this: for (i in seq(1:nrow(dataframe1))) {

Dear All, Suppose I have the following dataframe: country;weight;group bul;10;1 cze;12;1 grc;12;1 hun;12;1 prt;12;1 rom14;1 fra;29;2 ita;29;2 gbr;29;2 aut;10;3 bel;12;3 The "group" variable denotes the id-number of a group of countries. How can I re-label the groups in the descending order of their cumulative "weight", which wound be: country;weight;group fra;29;1 ita;29;1

Using the input below, can I do something more elegant (and more efficient) than the loop also listed below to pad strings to a width of 5? The true matrix is about 300K rows and 31 columns. ####################### #INPUT ####################### > temp DX1 DX2 DX3 1 13761 8125 49178 2 63371 v75 22237 3 51745 77703 93500 4 64081 32826 v72 5 78477 43828 87645 >