search for: pengyu

I don't find a function to print a string to file. Would somebody let me know what function I should use?

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

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

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?

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

...o optimizations, but > doesn't emit optnone and nounwind attributes) and later run opt on the > final bitcode. Note that the results might not be the same as running a > proper LTO build because of different pass manager pipelines. > > On Mon, Jan 28, 2019 at 11:24 AM Peng Yu <pengyu.ut at gmail.com> wrote: > >> 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 w...

...he bitcode I complied with gllvm and it seems to work fine under lli. The only issues is to make sure you load all the (external) libraries the bitcode needs. I highly suggest you run a debug version of lli under a debugger and see what exactly happens. On Mon, Jan 28, 2019 at 12:45 PM Peng Yu <pengyu.ut at gmail.com> wrote: > It seems that it does not really work. When I run the generated .bc > file, it gives me the following error. Do you what is wrong? > > $ lli bash.bc > Stack dump: > 0. Program arguments: lli bash.bc > 0 lli 0x00000001051539...

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

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) >

I'm thinking of using external program 'grep' and pipe() to do so. But I'm wondering if there is a more efficient way to do so purely in R

I'm wondering where I can find the detailed descriptions on R memory management. Understanding this could help me understand the runtime of R program. For example, depending on how memory is allocated (either allocate a chuck of memory that is more than necessary for the current use, or allocate the memory that is just enough for the current use), the performance of the following program could

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

length(unique(c(1,2,2)))==length(c(1,2,2)) I use the above test to test if all the elements in a vector are unique. But I'm wondering if there is a convenient function to do so in R library.

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

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

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",

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

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

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

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