Displaying 20 results from an estimated 20000 matches similar to: "Why 'return' is needed in R?"
2009 Nov 19
4
Is there an variant of apply() that does not return anything?
There are a few version of apply() (e.g., lapply(), sapply()). I'm
wondering if there is one that does not return anything but just
silently apply a function to the list argument.
For example, the plot function is applied to each element in 'alist'.
It is redundant to return anything from apply.
apply(alist,function(x){ plot each element of alist})
2009 Sep 14
2
What are the return values of aov?
Hi,
I don't quite understand what are the return values of aov. I know
that it has 'coefficients'. But I need to know what all the other
return values are. Can somebody let me know how to figure them?
Value:
An object of class 'c("aov", "lm")' or for multiple responses of
class 'c("maov", "aov", "mlm",
2009 Aug 10
5
Example scripts for R Manual
Hi,
I am wondering if some experienced users would help put the
ready-to-run code of the examples in the manuals. It would help new
users learn R faster by putting all the examples in an ready-to-run R
script file. Can somebody help do so sometime and post the code along
with the pdf manuals?
http://cran.r-project.org/manuals.html
Regards,
Peng
2009 Dec 18
4
How to print to file?
I don't find a function to print a string to file. Would somebody let
me know what function I should use?
2010 Feb 03
5
How to export the examples in help(something) to a file?
Some examples in the help page are too long to be copied from screen.
Could somebody let me know some easy way on how to extract the example
to a file so that I can play with them?
2010 Jan 21
3
Anova unequal variance
I found this paper on ANOVA on unequal error variance. Has this be
incorporated to any R package? Is there any textbook that discuss the
problem of ANOVA on unequal error variance in general?
http://www.jstor.org/stable/2532947?cookieSet=1
2010 Jan 01
5
How to not to terminate read.table if the input file is empty?
read.table terminates the program if the input file is empty. Is there
way to let the program continue and return me a NULL instead of
terminating the program?
$ Rscript read_empty.R
> read.table("empty_data.txt")
Error in read.table("empty_data.txt") : no lines available in input
Execution halted
$ cat read_empty.R
read.table("empty_data.txt")
$ cat
2012 Dec 30
4
[LLVMdev] git repository of the tutorial
Hi,
I'm learning the tutorial.
http://llvm.org/docs/tutorial/
I'm wondering if there is already a git repository of the examples in
the tutorial so that I don't have to copy the code from the webpage.
Thanks!
--
Regards,
Peng
2009 Sep 14
3
How to refer to the last a few rows?
Hi,
x=matrix(1:60,nr=6)
I can refer the last 2 rows by
x[5:6,]
If I don't know the total number of rows is 6, is there a way to refer
the last 2 rows?
Regards,
Peng
2019 Jan 28
2
How to generate .bc file using configure && make on Mac OS X?
>
> but doesn't emit optnone and nounwind attributes
>
s/nounwind/noinline
On Mon, Jan 28, 2019 at 11:35 AM Jakub (Kuba) Kuderski <
kubakuderski at gmail.com> wrote:
> As far as I understand, gllvm doesn't run LTO pipeline or any cross-module
> optimization, and the optimization level provided is only used to compile
> each Translation Unit separately.
> If you
2009 Oct 02
3
How to get duplicated items in a vector?
Hi,
> x=c(rep(1,3),rep(3,2))
> x
[1] 1 1 1 3 3
> duplicated(x)
[1] FALSE TRUE TRUE FALSE TRUE
>
As shown in the above code, 'duplicated' doesn't return 'F' for the
first '1' and first '3' in 'x'. I am wondering if there is a function
that can return an indicator for any element whether it appears in a
vector twice or more.
Regards,
Peng
2009 Nov 03
3
How to exclude certain columns by column names?
I can exclude columns by column number using '-'. But I wondering if
there is an easy way to exclude some columns by column names.
> x=cbind(c(1,2),c(3,4))
> x
[,1] [,2]
[1,] 1 3
[2,] 2 4
> colnames(x)=c('a','b')
> x
a b
[1,] 1 3
[2,] 2 4
> x[,-'a']
Error in -"a" : invalid argument to unary operator
> x[,-1]
[1] 3 4
2009 Aug 06
5
Is there a 'vi' mode in R?
Hi,
I'm wondering if R provide a vi mode in the command line just like
other shells such as bash do. Can somebody let me know?
Regards,
Peng
2009 Sep 06
2
How to pop up the graphics window from Rscript?
Hi,
I am wondering how to pop up the graphics window from Rscript. I run
the following code, but I don't see the graphics window, even
transiently.
Regards,
Peng
$ Rscript plot.R
> x=1:10
> y=1:10
> plot(x,y)
>
2009 Sep 05
2
How to 'apply' on multiple arguments?
Hi,
I am wonder if there is a function similar 'apply' but it could accept
multiple arguments?
For example, I have the following matrix.
x=matrix(1:6,nr=2)
y=matrix(1:6,nr=2)
I want to find a function that can be used to compute the linear
regression for each pair of rows in the two matrices?
multiple_apply(x,y,1,function(u,v){lm(u ~ v)}
That is, I wound like something like the above
2015 Jan 06
2
[LLVMdev] Are there manpages for llvm?
Hi,
I have llvm installed through MacPorts. But I don't see macports
installed. Are there supposed to be manpages of commands like lli
installed?
--
Regards,
Peng
2009 Sep 17
2
What does model.matrix() return?
Hi,
I don't understand what the meaning of the following lines returned by
model.matrix(). Can somebody help me understand it? What can they be
used for?
attr(,"assign")
[1] 0 1 2 2
attr(,"contrasts")
attr(,"contrasts")$A
[1] "contr.treatment"
attr(,"contrasts")$B
[1] "contr.treatment"
Regards,
Peng
> a=2
> b=3
> n=4
2009 Dec 10
3
How to figure out which the version of split is used?
There are a number of functions that are dispatched to from split().
> methods('split')
[1] split.data.frame split.Date split.default split.POSIXct
Is there a way to figure out which of these variants is actually
dispatched to when I call split? I know that if the argument is of the
type data.frame, split.data.frame will be called? Is it the case that
if the argument is not
2019 Jan 28
2
How to generate .bc file using configure && make on Mac OS X?
This works great.
> You can also try using the gllvm wrapper: https://github.com/SRI-CSL/gllvm ; it's quite reliable and easy to use in my experience.
Just to be sure. Only one version of bc file will be generated that
corresponds to the compiler options provide at configure?
The original approach using ld.gold will provide several .bc files
that correspond to different stages of the
2009 Nov 05
4
The equivalence of t.test and the hypothesis testing of one way ANOVA
I read somewhere that t.test is equivalent to a hypothesis testing for
one way ANOVA. But I'm wondering how they are equivalent. In the
following code, the p-value by t.test() is not the same from the value
in the last command. Could somebody let me know where I am wrong?
> set.seed(0)
> N1=10
> N2=10
> x=rnorm(N1)
> y=rnorm(N2)
> t.test(x,y)
Welch Two Sample t-test
data: