Displaying 20 results from an estimated 2000 matches similar to: "select rows with identical columns from a data frame"
2013 Jan 04
4
non-consing count
Hi,
to count vector elements with some property, the standard idiom seems to
be length(which):
--8<---------------cut here---------------start------------->8---
x <- c(1,1,0,0,0)
count.0 <- length(which(x == 0))
--8<---------------cut here---------------end--------------->8---
however, this approach allocates and discards 2 vectors: a logical
vector of length=length(x) and an
2012 Oct 18
3
how to concatenate factor vectors?
How do I concatenate two vectors of factors?
--8<---------------cut here---------------start------------->8---
> a <- factor(5:1,levels=1:9)
> b <- factor(9:1,levels=1:9)
> str(c(a,b))
int [1:14] 5 4 3 2 1 9 8 7 6 5 ...
> str(unlist(list(a,b),use.names=FALSE))
Factor w/ 9 levels "1","2","3","4",..: 5 4 3 2 1 9 8 7 6 5 ...
2012 Aug 30
3
apply --> data.frame
Is there a way for an apply-type function to return a data frame?
the closest thing I think of is
foo <- as.data.frame(sapply(...))
names(foo) <- c(....)
is there a more "elegant" way?
Thanks!
--
Sam Steingold (http://sds.podval.org/) on Ubuntu 12.04 (precise) X 11.0.11103000
http://www.childpsy.net/ http://palestinefacts.org http://dhimmi.com
http://honestreporting.com
2006 Mar 17
6
removing NA from a data frame
Hi,
It appears that deal does not support missing values (NA), so I need to
remove them (NAs) from my data frame.
how do I do this?
(I am very new to R, so a detailed step-by-step
explanation with code samples would be nice).
Some columns (variables) have quite a few NAs, so I would rather drop
the whole column than sacrifice all the rows (observations) which have
NA in that column.
How do I
2012 Dec 27
4
vectorization & modifying globals in functions
I have the following code:
--8<---------------cut here---------------start------------->8---
d <- rep(10,10)
for (i in 1:100) {
a <- sample.int(length(d), size = 2)
if (d[a[1]] >= 1) {
d[a[1]] <- d[a[1]] - 1
d[a[2]] <- d[a[2]] + 1
}
}
--8<---------------cut here---------------end--------------->8---
it does what I want, i.e., modified vector d 100 times.
2006 May 11
3
cannot turn some columns in a data frame into factors
Hi,
I have a data frame df and a list of names of columns that I want to
turn into factors:
df.names <- attr(df,"names")
sapply(factors, function (name) {
pos <- match(name,df.names)
if (is.na(pos)) stop(paste(name,": no such column\n"))
df[[pos]] <- factor(df[[pos]])
cat(name,"(",pos,"):",is.factor(df[[pos]]),"\n")
2012 Nov 07
3
c weirdness
is there a way to avoid c() appending ".0" and ".1" to seed?
--8<---------------cut here---------------start------------->8---
> c("nons"=1, "seed"=3)
nons seed ## good!
1 3
> c("nons"=1, "seed"=tab[1])
nons seed.0 ## don't want ".0"!
1 2344600
>
2012 Aug 27
1
write.matrix.csr data conversion
> write.matrix.csr(mx, y = y, file = file)
> table(y)
0 1
5194394 23487
$ cut -d' ' -f1 f | sort | uniq -c
23487 2
5194394 1
i.e., 0 is written as 1 and 1 is written as 2.
why?
is there a way to disable this?
--
Sam Steingold (http://sds.podval.org/) on Ubuntu 12.04 (precise) X 11.0.11103000
http://www.childpsy.net/ http://palestinefacts.org
2012 Nov 09
4
as.data.frame(do.call(rbind,lapply)) produces something weird
The following code:
--8<---------------cut here---------------start------------->8---
> myfun <- function (x) list(x=x,y=x*x)
> z <- as.data.frame(do.call(rbind,lapply(1:3,function(x) c(a=paste("a",x,sep=""),as.list(unlist(list(b=myfun(x),c=myfun(x*x*x))))))))
> z
a b.x b.y c.x c.y
1 a1 1 1 1 1
2 a2 2 4 8 64
3 a3 3 9 27 729
2012 Sep 19
2
drop zero slots from table?
I find myself doing
--8<---------------cut here---------------start------------->8---
tab <- table(...)
tab <- tab[tab > 0]
tab <- sort(tab,decreasing=TRUE)
--8<---------------cut here---------------end--------------->8---
all the time.
I am wondering if the "drop 0" (and maybe even sort?) can be effected by
some magic argument to table() which I fail to discover
2011 Feb 15
4
string parsing
I am trying to get stock metadata from Yahoo finance (or maybe there is
a better source?)
here is what I did so far:
yahoo.url <- "http://finance.yahoo.com/d/quotes.csv?f=j1jka2&s=";
stocks <- c("IBM","NOIZ","MSFT","LNN","C","BODY","F"); # just some samples
socket <-
2012 Jul 13
1
LiblineaR: read/write model files?
How do I read/write liblinear models to files?
E.g., if I train a model using the command line interface, I might want
to load it into R to look the histogram of the weights.
Or I might want to train a model in R and then apply it using a command
line interface.
--
Sam Steingold (http://sds.podval.org/) on Ubuntu 12.04 (precise) X 11.0.11103000
http://www.childpsy.net/
2011 Jul 11
1
plot means ?
Hi,
I need this plot:
given: x,y - numerical vectors of length N
plot xi vs mean(yj such that |xj - xi|<epsilon)
(running mean?)
alternatively, discretize X as if for histogram plotting and plot mean y
over the center of the histogram group.
is there a simple way?
thanks!
--
Sam Steingold (http://sds.podval.org/) on CentOS release 5.6 (Final) X 11.0.60900031
http://thereligionofpeace.com
2012 Mar 14
2
sum(hist$density) == 2 ?!
> x <- rnorm(1000)
> h <- hist(x,plot=FALSE)
> sum(h$density)
[1] 2 ----------------------------- shouldn't it be 1?!
> h <- hist(x,plot=FALSE, breaks=(-4:4))
> sum(h$density)
[1] 1 ----------------------------- now it's 1. why?!
--
Sam Steingold (http://sds.podval.org/) on Ubuntu 11.10 (oneiric) X 11.0.11004000
http://www.childpsy.net/ http://www.memritv.org
2012 Dec 04
3
list to matrix?
How do I convert a list to a matrix?
--8<---------------cut here---------------start------------->8---
list(c(50000, 101), c(1e+05, 46), c(150000, 31), c(2e+05, 17),
c(250000, 19), c(3e+05, 11), c(350000, 12), c(4e+05, 25),
c(450000, 19), c(5e+05, 16))
as.matrix(a)
[,1]
[1,] Numeric,2
[2,] Numeric,2
[3,] Numeric,2
[4,] Numeric,2
[5,] Numeric,2
[6,] Numeric,2
[7,]
2011 Feb 15
1
all.equal: subscript out of bounds
When I do
> all(all$X.Time == all$Y.Time);
[1] TRUE
as expected, but
> all.equal(all$X.Time,all$Y.Time);
Error in target[[i]] : subscript out of bounds
why?
thanks!
--
Sam Steingold (http://sds.podval.org/) on CentOS release 5.3 (Final)
http://mideasttruth.com http://honestreporting.com http://dhimmi.com
http://jihadwatch.org http://pmw.org.il http://ffii.org
The dark past once was the
2017 Nov 09
2
[R-pkgs] Release of ess 0.0.1
> * Jorge Cimentada <pvzragnqnw at tznvy.pbz> [2017-11-09 00:02:53 +0100]:
>
> I'm happy to announce the release of ess 0.0.1 a package designed to
> download data from the European Social Survey
Given the existence of ESS (Emacs Speaks Statistics -
https://ess.r-project.org/) the package name "ess" seems unfortunate.
--
Sam Steingold (http://sds.podval.org/) on
2012 Sep 19
4
where are these NAs coming from?
I see this:
--8<---------------cut here---------------start------------->8---
> length(which(is.na(z$language)))
[1] 0
> locals <- z[z$country == mycountry,]
> length(which(is.na(locals$language)))
[1] 229
--8<---------------cut here---------------end--------------->8---
where are those locals without the language coming from?!
--
Sam Steingold (http://sds.podval.org/) on
2012 Feb 13
1
entropy package: how to compute mutual information?
suppose I have two factor vectors:
x <- as.factor(c("a","b","a","c","b","c"))
y <- as.factor(c("b","a","a","c","c","b"))
I can compute their entropies:
entropy(table(x))
[1] 1.098612
using
library(entropy)
but it is not clear how to compute their mutual information
2012 Apr 04
2
recover lost global function
Since R has the same namespace for functions and variables,
> c <- 1
kills the global function, which can be restored by
> c <- get("c",mode="function")
Is there a way to prevent R from overriding globals
or at least warning when I do that
or at least warning when I replace a functional value with non-functional?
thanks.
--
Sam Steingold (http://sds.podval.org/)