Displaying 20 results from an estimated 700 matches similar to: "change values in data frames"
2012 Oct 04
4
Subsetting a group of data
Hi,
I am making my way down the learning curve of R, and find it a great
language with so many helpful users!
Below is an example of what I'm trying to do, but can't quite figure out the
right path to go down.
Here's what I have:
Main is a time series of data with columns Cola and Colb
Cola Colb
1 1 1
2 1
2009 Jul 12
2
Nonlinear Least Squares nls() programming help
Hi, I am trying to use the nls() function to closely approximate a vector of
values, colC and I'm running into trouble. I am not sure how if I am asking
the program to do what I think its doing, because the same minimization in
Excel's Solver does not run into problems. If anyone can tell me what is
going wrong, and why I'm getting a singular convergence(7) error, please
tell me. I
2012 Jul 11
4
Help with loop
Hi,
I have two dataframes:
The first, df1, contains some missing data:
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
The second, df2, contains the following:
cola colb colc cold cole
1 1.4 0.8 0.02 1.6 0.6
I'm wanting all missing data in df1$cola to be replaced by the value of
df2$cola.
2011 Aug 03
2
Error message for MCC
Greetings all,
I am getting an error message that is stifling me.
Any ideas?
> ## Define Directories ##
> load_from <- "/home/mcc/Dropbox/abrodsky/kegg_combine_data/"
> save_to <- "/home/mcc/Dropbox/abrodsky/ttest_results/"
>
> ###############################
> ## Define Columns To Compare ##
> compareA <- "log_b_rich"
> compareB
2013 Apr 30
2
R Function to extract columnNames
Hi,
May be this helps:
funcName<- function(df1, x){
?whatCol=df1[[x]]
?print("Got it")
?print(whatCol)
?}
?
funcName(df,"ColA")
#[1] "Got it"
#[1] 1 2 3 4 5
? funcName(df,"ColB")
#[1] "Got it"
#[1] A B C D E
#Levels: A B C D E
A.K.
>I am trying to extract the 2nd column from a dataframe using a function
called funcName. Note this is an
2005 Sep 09
3
how to do something like " subset(mat, ("col1">4 & "col2">4)) "
Dear all,
I have a problem with the "subset()" function. I spent all day yesterday
with a collegue to solve it and we did not find a satisfying solution (even
in the archived mails), so I ask for your help.
Let's say (for a simple example) a matrix mat:
R> mat
cola colb colc
[1,] 1 4 7
[2,] 2 5 8
[3,] 3 6 9
My goal is to select the lines of the matrix on the basis of the
2011 Aug 05
2
Which is more efficient?
Greetings all,
I am curious to know if either of these two sets of code is more efficient?
Example1:
## t-test ##
colA <- temp [ , j ]
colB <- temp [ , k ]
ttr <- t.test ( colA, colB, var.equal=TRUE)
tt_pvalue [ i ] <- ttr$p.value
or
Example2:
tt_pvalue [ i ] <- t.test ( temp[ , j ], temp[ , k ], var.equal=TRUE)
-------------
I have three loops, i, j, k.
One to test the all of
2011 Jun 10
2
Sorting Data Frame Without Loop
Hello all!
I am currently trying to sort a data frame in a particular way, but I am having some difficulties with this. Specifically I want to sort the below dataset in such a way that there is only one line per ProteinID and if there are multiple GeneID or GeneName entries for a single proteinID, that they be concatenated with a comma separating them. The way I have done it earlier worked fine
2010 Dec 09
2
Reshape Columns
Hello,
I have a general formatting question. I have two columns of data:
ColA <- c("m", "m", "m", "m")
ColB<- c("d","d","d","d")
And I would like to reorder them into a new column that looks like this:
ColC<-
2013 Apr 03
2
Creating data frame from individual files
Dear Group:
I have 72 files (.txt).
Each file has 2 columns and column 1 is always identical for all 70 files.
Each file has 90,799 rows and is standard across all files.
I want to create a matrix 40(rows) x 70 columns.
I tried :
temp = list.files(pattern="*.txt")
named.list <- lapply(temp, read.delim)
library(data.table)
files.matrix <-rbindlist(named.list)
>
2010 Feb 10
2
sum sections of data of different lengths from within a data frame
Dear R Help:
I am trying to sum data from one column in a dataframe based on a value in another. I do not know how to do this easily in R.
For example:
Col A Col B
1 0
3 0
2 1
2 0
1 0
4 0
1 1
9 1
3 0
5 0
2 1
I would like to cumsum the values in Col A for all rows where Col B is 0, and a value of 1 in Col B will reset
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]]
2006 Apr 12
0
New class: data.table
Hi,
Following previous discussion on this list
(http://tolstoy.newcastle.edu.au/R/devel/05/12/3439.html) I have created a
package as suggested, and uploaded it to CRAN incoming : data.table.tar.gz.
** Your comments and feedback will be very much appreciated. **
>From help(data.table) :
This class really does very little. The only reason for its existence is
that the white book specifies
2005 Aug 22
3
read a table ignoring specific rows ?
Dear R users,
First of all sorry for this question, surely quite naive.
(I searched on the R site but was unable to find by myself).
I have a table, called infile :
1 2 3
4 5 6
7 8 9
I would like to read it and ignore the rows with 1st element > 3
I do it now with a for loop, and it's ok,
but I was expecting something simpler, like :
intable = read.table(infile);
newtable =
2011 May 28
1
newbie xml parsing question
I am trying to read some data off the zillow site. Newbie to xml, html,
parsing and the xml package. I've been able to load the web page I'm
interested with the following code but I'm not sure of the next step to get
the information I'm interested in into R :
library(XML)
url <- "http://www.zillow.com/homes/511 W Lafayette St, Norristown, PA_rb"
doc <-doc <-
2015 Feb 24
2
intercalar elementos de vectores
Gracias, Carlos.
Habia pensado en algo similar usando sapply():
sapply(seq(1, ncol(vtmp), by = 2), function(i) c(rbind(as.character(vtmp[,
i]), as.character(vtmp[, i+1]))))
Dependiendo de la dimension de los datos, quizas mapply() sea mas eficiente
que sapply().
Saludos cordiales,
Jorge.-
2015-02-25 1:01 GMT+11:00 Carlos Ortega <cof en qualityexcellence.es>:
> Hola,
>
> Este
2010 Nov 05
1
How to extract particular rows and column from a table
Hello,
I'm a new user of R. I've a very big table like the following structure
(suppose the variable name with "aa"). From this table I want to make a new
table which'll contain just two column with V2 and V6 with some particular
rows( Suppose, variable name with "bb"). I'd like to mention V2 column is
representing the id that correspond to the column V6 whis
2013 May 26
0
SAPPLY function for COLUMN NULL
colnames(dd)
#[1] "col1" "colb"
null_vector<- colnames(dd)
sapply(null_vector,makeNull,dd)
#???? col1 colb
#[1,]?? NA??? 4
#[2,]??? 2?? NA
#[3,]??? 3??? 2
#[4,]??? 4?? NA
#[5,]??? 1??? 4
#[6,]?? NA??? 5
#[7,]??? 1??? 6
A.K.
>I am trying to make a column value in a dataframe = NA if there is a 0
or high value in that column. I need to do this process repeatedly,
hence
2015 Feb 24
2
intercalar elementos de vectores
Excelente! Ahora corre muy rápido. No conocía ese método, creo que me va a
resultar muy útil.
Muchas gracias y saludos.
Fernando Macedo
El 24/02/15 a las 10:51, Jorge I Velez escribió:
Fernando,
Podrias intentar
R> a <- rep('a', 5)
R> b <- rep('b', 5)
R> a
[1] "a" "a" "a" "a" "a"
R> b
[1] "b"
2012 Jul 14
3
Can't understand syntax
OK, I need help!!
I've been searching, but I don't understand the logic of some this
dataframe addressing syntax.
What is this type of code called?
test [["v3"]] [is.na(test[["v2"]])] <-10 #choose column v3 where column v2
is == 4 and replace with 10
and where is it documented?
The code below works for what I want to do (find the non-missing value in a
row),