Displaying 20 results from an estimated 20000 matches similar to: "Naming an object after another object...can it be done?"
2012 Dec 25
5
aggregate / collapse big data frame efficiently
Hi,
I need to aggregate rows of a data.frame by computing the mean for rows with the same factor-level on one factor-variable;
here is the sample code:
x <- data.frame(rep(letters,2), rnorm(52), rnorm(52), rnorm(52))
aggregate(x, list(x[,1]), mean)
Now my problem is, that the actual data-set is much bigger (120 rows and approximately 100.000 columns) ? and it takes very very long
2009 Aug 12
2
Symbolic references - passing variable names into functions
Hello All,
I am trying to write a function which would operate on columns of a
dataframe specified in parameters passed to that function.
f = function(dataf, col1 = "column1", col2 = "column2") {
dataf$col1 = dataf$col2 # just as an example
}
The above, of course, does not work as intended. In some languages one
can force evaluation of a variable, and then
2006 Nov 30
4
Quicker way of combining vectors into a data.frame
Hi,
In a function, I compute 10 (un-named) vectors of reasonable length
(4471 in the particular example I have to hand) that I want to combine
into a data frame object, that the function will return.
This is very slow, so *I'm* doing something wrong if I want it to be
quick and efficient, though I'm not sure what the best way to do this
would be.
I know it is the combining into data
2008 Jul 17
4
help with data layout
Hello list
I have been given some Excel sheets with data laid like this:
Col1 Col2
A 3
2
3
B 4
5
4
C 1
4
3
I was hoping to import this into R as a csv and then get the mean and SD for each letter in column 1.
Could someone give me some guidance on best to approach this?
Thanks
Iain
2009 Dec 20
2
Remove rows in a matrix that match rows in another matrix
Dear R Community,
The following seems like a simple problem, but I''ve been stuck on it for
some time, with no luck using matching or subsetting functions. I''m trying
to remove the rows from a large matrix that match rows in another large
matrix. A (small scale) example:
col1<-c("A", "B", "C", "D")
col2<-c("A",
2013 Feb 28
2
Fortune?
I think the rule is that you can do anything as long as you don't
complain. If you want to complain, you must follow the instructions.
-- Jari Oksanen in
Re: [Rd] Keeping up to date with R-devel
--
Patrick Burns
pburns at pburns.seanet.com
twitter: @burnsstat @portfolioprobe
http://www.portfolioprobe.com/blog
http://www.burns-stat.com
(home of:
'Impatient R'
'The R
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
===>
2012 Oct 18
4
speeding read.table
R 2.15.1
OS X
Colleagues,
I am reading a 1 GB file into R using read.table. The file consists of 100 tables, each of which is headed by two lines of characters.
The first of these lines is:
TABLE NO. 1
The second is a list of column headers.
For example:
TABLE NO. 1
COL1 COL2 COL3 COL4 COL5 COL6 COL7 COL8 COL9 COL10
2011 Sep 12
3
Solve your R problems
R-help is all about solving R problems.
So here ya go:
http://www.portfolioprobe.com/2011/09/12/solve-your-r-problems/
--
Patrick Burns
pburns at pburns.seanet.com
twitter: @portfolioprobe
http://www.portfolioprobe.com/blog
http://www.burns-stat.com
(home of 'Some hints for the R beginner'
and 'The R Inferno')
2012 May 24
3
transform 1 col to 2 col
Dear All
How can I transform 1 column to 2 columns in R?
211217_s_at
GO:0005249
211217_s_at
GO:0005251
211217_s_at
GO:0005515
211217_s_at
GO:0015271
211217_s_at
GO:0030955
211217_s_at
GO:0005249
211217_s_at
GO:0005251
211217_s_at
GO:0005515
211217_s_at
GO:0015271
211217_s_at
GO:0030955
Best Wishes,
Soheila
[[alternative HTML version deleted]]
2011 Jan 24
2
how to slice a zoo object
Hi
Would anyone have any pointers on how to slice up a large zoo table. I
have the following structure: -
> str(ZOO_OBJ)
?zoo [1:632, 1:83] 30.4 30.4 30.4 30.4 30.3 ...
?- attr(*, "dimnames")=List of 2
??..$ : NULL
??..$ : chr [1:83] "COL1" "COL2" "COL3" "COL4" ...
?- attr(*, "index")= POSIXct[1:632], format: "2009-05-01
2011 Mar 16
3
making dataframes
Dear all,
I have a dataframe which looks like this (dummy):
date<-c("jan", "feb", "mar", "apr", "may", "june", "july",
"aug","sep","oct","nov","dec")
col1<-c(8.2,5.4,4.3,4.1,3.1,2.5,1.1,4.5,3.2,1.9,7.8,6.5)
col2<-c(3.1,2.3,4.7,6.9,7.5,1.1,3.6,8.5,7.5,2.5,4.1,2.3)
2011 Oct 06
3
Running *slow*
Anyone got any hints on how to make this code more efficient? An early
version (which to be fair did more than this one is) ran for 330 hours
and produced no output.
I have a two column table, Dat, with 12,000,000 rows and I want to
produce a lookup table, ltable, in a 1 dimensional matrix with one
copy of each of the values in Dat:
for (i in 1:nrow(Dat))
{
for (j in 1:2)
{
#If next
2012 Aug 13
4
if else elseif for data frames
Hi all,
It seems like I cannot use normal 'if' for data frames. What would be the
best way to do the following.
if data$col1='high'
data$col2='H'
else if data$col1='Neutral'
data$col2='N'
else if data$col='low'
data$col2='L'
else
#chuch a warning?
Note that col2 was not an existing column and was newly assigned for this
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,
2017 Aug 23
2
Comparing 2 dale columns
Dear R fellows,
I created a new column Date_flag to compare the dates of COL1 and COL2 using the code
below. But it showed that 5/1/15 is greater than 6/1/2014 and 5/1/2015 greater than
7/1/2014 despite the year is greater. How do I fix that? I did try to format as %y/%m/%d
but it does not fix that.
data$Date_Flag <- ifelse(data$COL2 > data$COL1, 0,1)
COL1 COL2
6/1/14
2013 Apr 06
1
Value at Risk using a volatility model?
Hi,
I want to calculate the Value at Risk with using some distirbutions and a
volatility model.
I use the following data(http://uploadeasy.net/upload/cdm3n.rar) which are
losses (negative returns) of a company of approx. the last 10 years. So I
want to calculated the Value at Risk, this is nothing else than the
quantile. Since I have losses I consider the right tail of the distribution.
Consider
2010 Dec 24
1
How to specify ff object filepaths when reading a CSV file into a ff data frame.
Hi,
The read.csv.ffdf function in package ff will create the ff object
physical file in the default directories, I am trying to let the files
created in the paths users specify, I think the point is to make use
of the asffdf_args parameter,
I have a test CSV file named D:\rtemp\fftest.csv, the content of the
file is as following:
col1,col2,col3
1,"amber",2.4
2,"linda",4.5
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 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],