Displaying 20 results from an estimated 10000 matches similar to: "seq_along and rep_along"
2009 Jul 09
1
bug in seq_along
Using the IRanges package from Bioconductor and somewhat recent R-2.9.1.
ov = IRanges(1:3, 4:6)
length(ov) # 3
seq(along = ov) # 1 2 3 as wanted
seq_along(ov) # 1!
I had expected that the last line would yield 1:3. My guess is that
somehow seq_along don't utilize that ov is an S4 class with a length
method.
The last line of the *Details* section of ?seq has a typeo. Currently
it is
2010 Sep 03
1
'seq' help page: seq_length -> seq_len?
In the Value section of the 'seq' help page it says
'seq_along' and 'seq_length' always return an integer vector.
I believe it should be
'seq_along' and 'seq_len' always return an integer vector.
as there are no seq_length function?
Best, Niels
--
Niels Richard Hansen Web: www.math.ku.dk/~richard
Associate Professor
2010 Feb 25
3
behavior of seq_along
I'm trying to understand the behavior of seq_along in the following example:
x <- 1:5; sum(x)
y <- 6:10; sum(y)
data <- c(x,y)
S <- sum( data[seq_along(x)] )
S
T <- sum( data[seq_along(y)] )
T
Why is T != sum(y) ?
2007 Apr 03
1
Behavior of seq_along (was: Create a new var reflecting the order of subjects in existing var)
I am moving this from r-help to r-devel. Based on offline communications
with Jim, suppose dat is defined as follows:
set.seed(123)
dat <- data.frame(ID= c(rep(1,2),rep(2,3), rep(3,3), rep(4,4),
rep(5,5)), var1 =rnorm(17, 35,2), var2=runif(17,0,1))
# Then this ave call works as expected:
ave(dat$ID, dat$ID, FUN = function(x) seq_along(x))
# but this apparently identical calculation
2024 Jun 16
1
slowness when I use a list comprehension
This can be vectorized. Try
ix <- seq_along(vec2)
S_diff2 <- sapply(seq_len(N1-(N2-1)*ratio_sampling), \(j)
sum((vec1[(ix-1)*ratio_sampling+j] - vec2[ix])**2))
On Sun, Jun 16, 2024 at 11:27?AM Laurent Rhelp <laurentRHelp at free.fr> wrote:
>
> Dear RHelp-list,
>
> I try to use the package comprehenr to replace a for loop by a list
> comprehension.
>
> I
2017 Jun 23
1
R version 3.3.2, Windows 10: Applying a function to each possible pair of rows from two different data-frames
Hello,
Another way would be
n <- nrow(expand.grid(1:nrow(D1), 1:nrow(D2)))
D5 <- data.frame(distance=integer(n),difference=integer(n))
D5[] <- do.call(rbind, lapply(seq_len(nrow(D1)), function(i)
t(sapply(seq_len(nrow(D2)), function(j){
c(distance=sqrt(sum((D1[i,1:2]-D2[j,1:2])^2)),difference=(D1[i,3]-D2[j,3])^2)
}
))))
identical(D3, D5)
In my first answer I forgot to say that
2012 Nov 05
2
averaging a list of matrices element wise
Dear all,
I have a list of n matrices which all have the same dimension (r x s). What would be a fast/elegant way to calculate the element wise average? So result[1, 1] <- mean(c(raw[[1]][1, 1] , raw[[2]][1, 1], raw[[...]][1, 1], raw[[n]][1, 1]))
Here is my attempt.
#create a dummy dataset
n <- 3
r <- 5
s <- 6
raw <- lapply(seq_len(n), function(i){
matrix(rnorm(r * s), ncol =
2016 Dec 20
2
colnames for data.frame could be greatly improved
Hello,
colnames seems to be not optimized well for data.frame. It escapes
processing for data.frame in
if (is.data.frame(x) && do.NULL)
return(names(x))
but only when do.NULL true. This makes huge difference when do.NULL
false. Minimal edit to `colnames`:
if (is.data.frame(x)) {
nm <- names(x)
if (do.NULL || !is.null(nm))
return(nm)
else
2018 May 11
0
add one variable to a data frame
Sarah's solutions are good, and here's another, even more basic:
tmp1 <- unique(dat1$B)
tmp2 <- seq_along(tmp1)
dat1$C <- tmp2[ match( dat1$B, tmp1) ]
> dat1
N B C
1 1 29_log 1
2 2 29_log 1
3 3 29_log 1
4 4 27_cat 2
5 5 27_cat 2
6 6 1_log 3
7 7 1_log 3
8 8 1_log 3
9 9 1_log 3
10 10 1_log 3
11 11 3_cat 4
12 12 3_cat 4
As a single line
2019 Mar 02
1
stopifnot
A private reply by Martin made me realize that I was wrong about
stopifnot(exprs=TRUE) .
It actually works fine. I apologize. What I tried and was failed was
stopifnot(exprs=T) .
Error in exprs[[1]] : object of type 'symbol' is not subsettable
The shortcut
assert <- function(exprs) stopifnot(exprs = exprs)
mentioned in "Warning" section of the documentation similarly fails
2017 Aug 07
1
Has For bucle be impooved in R
Dear Jesus,
The difference is marginal when each code chunk does the same things. Your
for loop does not yields the same output as the lapply. Here is the cleaned
version of your code.
n<-10000
set.seed(123)
x<-rnorm(n)
y<-x+rnorm(n)
rand.data<-data.frame(x,y)
k<-100
samples <- split(sample(n), rep(seq_len(k),length=n))
library(microbenchmark)
microbenchmark(
"for"
2018 May 26
1
Grouping by 3 variable and renaming groups
Hello,
Sorry, but I think my first answer is wrong.
You probably want something along the lines of
sp <- split(priceStore_Grps, priceStore_Grps$StorePC)
res <- lapply(seq_along(sp), function(i){
sp[[i]]$StoreID <- paste("Store", i, sep = "_")
sp[[i]]
})
res <- do.call(rbind, res)
row.names(res) <- NULL
Hope this helps,
Rui Barradas
On 5/26/2018
2013 Oct 11
3
matrix values linked to vector index
Hi,
In the example you showed:
m1<- matrix(0,length(vec),max(vec))
1*!upper.tri(m1)
#or
?m1[!upper.tri(m1)] <-? rep(rep(1,length(vec)),vec)
#But, in a case like below, perhaps:
vec1<- c(3,4,5)
?m2<- matrix(0,length(vec1),max(vec1))
?indx <- cbind(rep(seq_along(vec1),vec1),unlist(tapply(vec1,list(vec1),FUN=seq),use.names=FALSE))
m2[indx]<- 1
?m2
#???? [,1] [,2] [,3] [,4] [,5]
2009 Jun 03
4
Excel Export in a beauty way
Hallo all,
I`ve read a lot of things in this forum about an Excel export via R. It is
no problem to export my data frames via write.table or write.xls (xls or
csv), but some things are not very convenient for me: I always have to
adjust the column with to see all the numbers or the text and there is no
frame between the cells. And I missing the possibility to make some headers
bold or coloured.
2011 Jan 31
1
str() on raster objects fails for certain dimensions
Hi,
str() on raster objects fails for certain dimensions. For example:
> str(as.raster(0, nrow=1, ncol=100))
'raster' chr [1, 1:100] "#000000" "#000000" "#000000" "#000000" ...
> str(as.raster(0, nrow=1, ncol=101))
Error in `[.raster`(object, seq_len(max.len)) : subscript out of bounds
This seems to do with how str() and
2018 May 11
3
add one variable to a data frame
Hi Sarah,
Thank you so much!! I got your good ideas.
Ding
-----Original Message-----
From: Sarah Goslee [mailto:sarah.goslee at gmail.com]
Sent: Friday, May 11, 2018 11:40 AM
To: Ding, Yuan Chun
Cc: r-help mailing list
Subject: Re: [R] add one variable to a data frame
[Attention: This email came from an external source. Do not open attachments or click on links from unknown senders or
2017 May 11
1
R-3.3.3/R-3.4.0 change in sys.call(sys.parent())
Here is a case where the current scheme fails:
> with(datasets::mtcars, xyplot(mpg~wt|gear)$call)
xyplot(substitute(expr), data, enclos = parent.frame())
Bill Dunlap
TIBCO Software
wdunlap tibco.com
On Thu, May 11, 2017 at 1:09 AM, Deepayan Sarkar <deepayan.sarkar at gmail.com>
wrote:
> On Wed, May 10, 2017 at 2:36 AM, William Dunlap via R-devel
> <r-devel at
2017 May 09
3
R-3.3.3/R-3.4.0 change in sys.call(sys.parent())
Some formula methods for S3 generic functions use the idiom
returnValue$call <- sys.call(sys.parent())
to show how to recreate the returned object or to use as a label on a
plot. It is often followed by
returnValue$call[[1]] <- quote(myName)
E.g., I see it in packages "latticeExtra" and "leaps", and I suspect it
used in "lattice" as well.
This idiom
2007 Oct 01
4
how to plot a graph with different pch
I am trying to plot a graph but the points on the graph should be
different symbols and colors. It should represent what is in the legend.
I tried using the points command but this does not work. Is there
another command in R that would allow me to use different symbols and
colors for the points?
Thank you kindly.
data(mtcars)
plot(mtcars$wt,mtcars$mpg,xlab= "Weight(lbs/1000)",
2011 Dec 13
1
How to add points to two plots parallelly ?
I am looking for ways to add points to three different plots in parallel.
I generate three scatter plots and name them as s3d1, s3d2 and s3d3
s3d1<-scatterplot3d(mtcars[,3],mtcars[,4],mtcars[,5],main="common",pch=20)
s3d2<-scatterplot3d(mtcars[,3],mtcars[,4],mtcars[,5],main="common",pch=20)