Displaying 20 results from an estimated 3000 matches similar to: ""A critique of R and S-PLUS""
2009 Aug 20
4
expanding 1:12 months to Jan:Dec
Dear R users
I would like to do some spreadsheet style expansion of dates. For
example, I would need to obtain a vector of months. I approached in an
obviously wrong way:
> paste(01:12)
[1] "1" "2" "3" "4" "5" "6" "7" "8" "9" "10" "11" "12"
> as.Date(paste(01:12),
2013 Apr 15
6
how to transform string to "Camel Case"?
Dear all,
Given the following vector:
> (z <- c('R project', 'hello world', 'something Else'))
[1] "R project" "hello world" "something Else"
I know how to obtain all capitals or all lower case letters:
> tolower(z)
[1] "r project" "hello world" "something else"
> toupper(z)
[1] "R
2009 May 15
4
replace "%" with "\%"
Dear all,
I'm trying to gsub() "%" with "\%" with no obvious success.
> temp1 <- c("mean", "sd", "0%", "25%", "50%", "75%", "100%")
> temp1
[1] "mean" "sd" "0%" "25%" "50%" "75%" "100%"
> gsub("%",
2011 Aug 10
3
convert 'list' to 'vector'?
Dear all
How does one convert a "non-symmetric" list to a vector? See below:
> x <- list()
> x[[1]] <- letters[1:5]
> x[[2]] <- letters[6:10]
> x[[3]] <- letters[11:12]
> x
[[1]]
[1] "a" "b" "c" "d" "e"
[[2]]
[1] "f" "g" "h" "i" "j"
[[3]]
[1] "k"
2012 May 05
3
alarm() doesn't beep
Dear all
I'd like to make a beeping sound in R, but alarm() doesn't beep? I
checked ?alarm but I couldn't find any pointers to system
configuration. Any ideas?
Regards
Liviu
> sessionInfo()
R version 2.14.2 (2012-02-29)
Platform: x86_64-pc-linux-gnu (64-bit)
locale:
[1] LC_CTYPE=en_US.UTF-8 LC_NUMERIC=C
[3] LC_TIME=en_US.UTF-8 LC_COLLATE=en_US.UTF-8
[5]
2011 Mar 06
4
sorting & subsetting a data.frame
Dear all
This may be obvious, but I cannot get it working. I'm trying to subset
& sort a data frame in one go.
x <- iris
x$Species1 <- as.character(x$Species)
##subsetting alone works fine
with(x, x[Sepal.Length==6.7,])
##sorting alone works fine
with(x, x[order(Sepal.Length, rev(sort(Species1))),])
##gets subsetted, but not sorted as expected
with(x, x[(Sepal.Length==6.7) &
2012 Jul 10
3
fill 0-row data.frame with 1 line of NAs
Dear all
Is there a simpler method to achieve the following: When I obtain an
empty data.frame after subsetting, I need for it to contain one line
of NAs. Here's a dummy example:
> (.xb <- iris[ iris$Species=='zz', ])
[1] Sepal.Length Sepal.Width Petal.Length Petal.Width Species
<0 rows> (or 0-length row.names)
> dim(.xb)
[1] 0 5
> (.xa <-
2011 Oct 03
2
extracting p-values in scientific notation
Dear all
How does print.htest display the p-value in scientific notation?
> (x <- cor.test(iris[[1]], iris[[3]]))
Pearson's product-moment correlation
data: iris[[1]] and iris[[3]]
t = 21.65, df = 148, p-value < 2.2e-16
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
0.8270 0.9055
sample estimates:
cor
0.8718
Above the p-value comes
2010 Oct 09
4
same random numbers in different sessions
Dear all
I'm using Xubuntu Lucid and I keep getting the same random numbers
whenever I start a new session of R. For example, I keep getting
> sample(1:1000, 1)
[1] 87
or
> rnorm(1:10)
[1] -1.3618103 0.4241701 1.0720076 0.2208145 -0.5375314 -0.4846588
[7] 0.7576768 0.6527407 -0.6868786 0.8718527
I expected that some set.seed() instruction woudl be present in a
config file in
2008 Dec 03
3
alternative way to replicate()
Dear all,
I'm looking for an alternative way to replicate the "2," string for an
x number of times, and end up with one string containing "2," x times.
I can partly achieve this using replicate().
> y <- rep("2,", times=3)
> y
[1] "2," "2," "2,"
The output that I am looking for is, however, "2,2,2,". I also tried
2009 Oct 14
3
currency conversion function?
Dear all
Is there any R function that would perform currency conversion using
up-to-date exchange rates? I would be looking for a function that
allows to download recent exchange rates (say, from Yahoo!) and then
use these in converting currencies (say, USD to EUR).
I am not sure whether r-sig-finance would be more appropriate, but the
(off-)topic feels general enough to me. Thank you
Liviu
--
2011 Aug 19
2
display only the top-right half of a correlation matrix?
Dear all
Is there an easy way to display only one half (top-right or
bottom-left) of a correlation matrix?
> require(Hmisc)
> rcorr(as.matrix(mtcars[ , 1:4]))
mpg cyl disp hp
mpg 1.00 -0.85 -0.85 -0.78
cyl -0.85 1.00 0.90 0.83
disp -0.85 0.90 1.00 0.79
hp -0.78 0.83 0.79 1.00
n= 32
P
mpg cyl disp hp
mpg 0 0 0
cyl 0 0 0
disp 0 0
2005 Apr 01
2
about get stdout from other program
Dear all R-helper,
if I want to use stdout from other language as my R program input ,which is
the best way for design the API,using Pipe function or produce a temporary
file,using scan function to read the file ?
thanks
Michael
2011 Aug 10
2
round() a data frame containing 'character' variables?
Dear all
It is difficult to use round(..., digits=2) on a data frame since one
has to first take care to remove non-numeric variables such as
'character' or 'factor':
> head(round(iris, 2))
Error in Math.data.frame(list(Sepal.Length = c(5.1, 4.9, 4.7, 4.6, 5, :
non-numeric variable in data frame: Species
> head(round(iris[1:4], 2))
Sepal.Length Sepal.Width Petal.Length
2011 Nov 24
2
proper work-flow with 'formula' objects and lm()
Dear all
I have a work-flow issue with lm(). When I use
> lm(y1~x1, anscombe)
Call:
lm(formula = y1 ~ x1, data = anscombe)
Coefficients:
(Intercept) x1
3.0001 0.5001
I get as expected the formula, "y1 ~ x1", in the print()ed results or
summary(). However, if I pass through a formula object
> (form <- formula(y1~x1))
y1 ~ x1
> lm(form, anscombe)
Call:
2011 Nov 24
2
understanding all.equal() output: "Mean relative difference"
Dear all
How should one parse all.equal() output? I'm specifically referring to
the 'mean relative difference' messages. For example,
> all.equal(pi, 355/113)
[1] "Mean relative difference: 8.491368e-08"
But I'm not sure how to understand these messages. When they're close
to 0 (or 1xe-16), then it's intuitive. But when they're big,
> all.equal(1, 4)
2012 Jun 21
4
convert 'character' vector containing mixed formats to 'Date'
Dear all
I have a 'character' vector containing mixed formats (thanks Excel!)
and I'd like to translate it into a default "%Y-%m-%d" Date vector.
x <- c("1/3/2005", "13/04/2004", "2/5/2005", "2/5/2005", "7/5/2007",
"22/04/2004", "21/04/2005", "20080430", "13/05/2003",
2009 Aug 16
2
bootstrapped correlation confint lower than -1 ?
Dear R users,
Does the results below make any sense? Can the the interval of the
correlation coefficient be between *-1.0185* and -0.8265 at 95%
confidence level?
Liviu
> library(boot)
> data(mtcars)
> with(mtcars, cor.test(mpg, wt, met="spearman"))
Spearman's rank correlation rho
data: mpg and wt
S = 10292, p-value = 1.488e-11
alternative hypothesis: true rho is not
2010 Nov 30
3
pca analysis: extract rotated scores?
Dear all
I'm unable to find an example of extracting the rotated scores of a
principal components analysis. I can do this easily for the un-rotated
version.
data(mtcars)
.PC <- princomp(~am+carb+cyl+disp+drat+gear+hp+mpg, cor=TRUE, data=mtcars)
unclass(loadings(.PC)) # component loadings
summary(.PC) # proportions of variance
mtcars$PC1 <- .PC$scores[,1] # extract un-rotated scores of
2006 May 19
2
"Pipelining" programs in R
Hello...
I would like to use R for 'pipelining' data among several programs. I'm
wondering how I can use R to call another program, feed that program a set
of parameters, and retrieve the output.
E.g., I have an executable that, when opened, prompts the user to enter a
set of parameters. The program then executes & prompts the user for the
name of an output file. I need to