search for: didactically

Hi, I read almost all I found in prior R-Help list about How to compare two regression line slopes. So, I made a didactic example to illustrate a solution cited by Ben Bolker: =============================================== Subject: Re: [R] How to compare two regression line slopes From: Ben Bolker (bol... at ufl.edu) Date: Jan 27, 2009 1:52:20 pm List: org.r-project.r-help

Hello, I want to compare a program before and after having run a FunctionPass. The purpose is merely didactic. What I would like to do is, during the runOnFunction() method, "save" somehow the instruction set and cfg of the function, run the optimization. and then compare the two codes, before and after the transformation. Is there an automatic way tho do that, or a suggested approach?

Hello everybody, I'm trying to build a function to illustrate, in 2D, the sequence of the "Single Link" algorithm (the purpose is merely didactic). The idea is to have the scatter of points on a graph. Iteratively, build the segments (with the "segments()" function, for each step). I simulated a data set "d", and created an object "r" using the

I wrote a R script say called computeCovarMatrix.R and i want to call and run this piece from Excel visual basic. does anyone know how to do that? thanks, KZ [[alternative HTML version deleted]]

Subsetting from a dataframe with only one variable returns a vector, not a dataframe. This seems somewhat inconsistent. Wouldn't it be better if subsetting would respect the structure completely? v1<-1:4 v2<-4:1 df1<-data.frame(v1) df2<-data.frame(v1,v2) sel1<-c(TRUE,TRUE,TRUE,TRUE) > df1[sel1,] [1] 1 2 3 4 > df2[sel1,] v1 v2 1 1 4 2 2 3 3 3 2 4 4 1 -- Erich

Hi folks, I have a dataframe df.vars with the follwing structure: var1 var2 var3 group Group is a factor. Now I want to standardize the vars 1-3 (actually - there are many more) by class, so I define z.mean.sd <- function(data){ return.values <- (data - mean(data)) / (sd(data)) return(return.values) } now I can call for each var z.var1 <- by(df.vars$var1, group,

some of you might be interested. i just uploaded the first release of my r-excel interface package to CRAN. it is in contributed extensions nonstandard extensions erich neuwirth -- Erich Neuwirth, Computer Supported Didactics Working Group Visit our SunSITE at http://sunsite.univie.ac.at Phone: +43-1-4277-38624 Fax: +43-1-4277-9386

some of you might be interested. i just uploaded the first release of my r-excel interface package to CRAN. it is in contributed extensions nonstandard extensions erich neuwirth -- Erich Neuwirth, Computer Supported Didactics Working Group Visit our SunSITE at http://sunsite.univie.ac.at Phone: +43-1-4277-38624 Fax: +43-1-4277-9386

In the windows version (RGui), is there a way to set the text displayed in the titlebar of the R window? When I have 2 instances of RGui running, it would be helpul if the titlebar could help to understand which is which. -- Erich Neuwirth, Computer Supported Didactics Working Group Visit our SunSITE at http://sunsite.univie.ac.at Phone: +43-1-4277-38624 Fax: +43-1-4277-9386

hist(rbinom(1000,10,0.5),col=2,xlim=c(0,10),ylim=c(0,300)) gives a histogram with "touching bars" hist(rbinom(100000,10,0.5),col=2,xlim=c(0,10),ylim=c(0,30000)) gives a histogram with space between the bars. is there a way to control the space betweent he bars easily? -- Erich Neuwirth, Computer Supported Didactics Working Group Visit our SunSITE at http://sunsite.univie.ac.at

typeof applied to a factor always seems to return "integer", independently of the type of the levels. This has a strange side effect. When a variable is "imported" into a data frame, its type changes. character variables automatically are converted to factors when imported into data frames. Here is an example: > v1<-1:3 >

FWIW, before all the examples are changed to data frame variants, I think there's fairly good reason to have at least _one_ example that does _not_ place variables in a data frame. The data argument in lm() is optional. And there is more than one way to manage data in a project. I personally don't much like lots of stray variables lurking about, but if those are the only variables out

I have a big contingency table, approximately of size 60*2*500*500, and I need to count the number of cells containing a count of 1 for each of the factors values defining the first dimension. Here is my attempt: tab1<-with(pisa1,table(CNT,GENDER,ISCOF,ISCOM)) tab2<-apply(tab1,1:4,function(x)ifelse(sum(x)==1,1,0)) tab3<-apply(tab2,1,sum) Computing tab2 is very slow. Is there a faster

On 14/04/13 18:40, Giacomo Tagliabue wrote: > I want to compare a program before and after having run a FunctionPass. > The purpose is merely didactic. What I would like to do is, during the I do a dump of the Module (Module.print) before and after running it through a PassManager (you could also use the Function.print method I think). You can put just a single pass in the PassManager to

RColorBrewer 0.1-1 is available on CRAN. The packages provides palettes for drawing nice maps shaded according to a variable as an R function. The palettes have been designed by and are copyrighted by the ColorBrewer project. An interactive palette selection tool byt the original designers is available at http://colorbrewer.org -- -- Erich Neuwirth, Computer Supported Didactics Working Group

RColorBrewer 0.1-1 is available on CRAN. The packages provides palettes for drawing nice maps shaded according to a variable as an R function. The palettes have been designed by and are copyrighted by the ColorBrewer project. An interactive palette selection tool byt the original designers is available at http://colorbrewer.org -- -- Erich Neuwirth, Computer Supported Didactics Working Group

My configuration is Windows XP, R-2.5.1patched. My standard browser in Windows is Firefox 2.0.6, and I am using htmlhelp. I have problems with starting the browser for displaying help. help("lm") works as it should when Firefox is already running. When I do help("lm") and the browser is not yet started, I get Error in shell.exec(url) :

David - information on calling R from within Mathematica can be found at the following link: http://www.mofeel.net/1164-comp-soft-sys-math-mathematica/13022.aspx HTH, Alan Kelly

with todays r-devel..tar.gz make distribution hangs on my win98 machine. this is the las message i see MAKE[2]: Leaving directory `/cygdrive/c/devel/R-devel/src/gnuwin32/bitmap/jpeg-6 b' cp Rbitmap.dll ../../../bin MAKE[1]: Leaving directory `/cygdrive/c/devel/R-devel/src/gnuwin32/bitmap' after that, the it seems that sed is running and somehow hangs. i do have the tools from brians

Is this warning given on purpose? > myconn<-textConnection("print(11*11)") > source(myconn) [1] 121 Warning message: In source(myconn) : argument 'encoding = "native.enc"' will be ignored Could it be omitted, since the docs state that encoding is only use if the corresponding argument is a file name or url? -- Erich Neuwirth, University of Vienna