similar to: How "else" works

I have a question about how apply() works for changing data values. I am using it to change NA values to zero, but the question applies to other value changing operations as well. If I have a dataframe "Dat" with columns "a", "b" and "c" and there are some NA values in every column: If I do: Dat$a[is.na(Dat$a)] <- 0 then all the NA values are changed

Is there a function to convert character strings to object references. For example, I want to name sets of objects based on scenarios and the types of data being stored. So the scenarios might be something like c("a", "b", "c"), the types of data might have names like c("pass.trp", "trk.trp", "cmute.trp"), and I want to assign data to

Saving Rdata files in a zip archive form can in some cases save a considerable amount of disk space. R has the zip.file.extract function to extract files from zip archives, but appears not to have any corresponding function to save in zipped form. (At least I have not been able to find anything in the help files or through searching the mail archives.) The system function can be used to call gzip

I had this problem too. The documentation for the winMenus says that these functions are part of the utils package. R must be loading this library after it sources in Rprofile. If you add library(utils) to the beginning of your .First function, it should take care of the problem. Brian Gregor, P.E. Transportation Planning Analysis Unit Oregon Department of Transportation Brian.J.GREGOR at

Hi R users, Maybe the question is too simple. In a IF ... ELSE ... statement "if(cond) cons.expr else alt.expr", IF and ELSE should be at the same line? For example, if (x1==12) { y1 <- 5 }else { y1 <- 3 } is right, while if (x1==12) { y1 <- 5 } else # Error: syntax error { y1 <- 3 } is wrong? Thanks -- Xiaohua Dai

First, here's the problem I'm working on so you understand the context. I have a data frame of travel activity characteristics with 70,000+ records. These activities are identified by unique chain numbers. (Activities are part of trip chains.) There are 17,500 chains. I use the chain numbers as factors to split various data fields into lists of chain characteristics with each element of

Why will this simple statement not work? I think I am following the documentation for if(cond) statements, and I have tried wrapping the cons.expr and alt.expr in {}, I get the same error. There is no example in the help file, and this is not covered in the Introduction to R, SimpleR or other tutorials I have looked into. mxx=max(cpx_list$nMV); mxy=max(trend_list$nMV); if (mxx>mxy) mxy=mxx

I was initially pretty shocked by the result in this question: https://stackoverflow.com/questions/57527434/when-do-i-need-parentheses-around-an-if-statement-to-control-the-sequence-of-a-f Briefly, the following returns 0, not 3 as might be expected: if (TRUE) { 0 } else { 2 } + 3 At first I thought it the question was simply one of syntax precedence, but I believe the result is too

Well, let's see: 1) You do not appear to understand basic flow control statements in R. Note that (from ?if): if(cond) expr if(cond) cons.expr else alt.expr where "cond A length-one logical vector that is not NA." Your cond is a vector of length nrow(DF), so you don't want if, you want ifelse(). Did you fail to show us your warning messages?? 2. Revising your code and

I am having trouble using get.bnddata() in the RArcInfo package. I installed the version 0.2 binary of the package for Windows and am using R 1.4.1 on Windows NT 4.0. I have had no problems importing and plotting arc data with get.arcdata() and plotarc(). plotpal() also works fine. I've been able to use get.arcdata(), get.labdata(), get.paldata(), get.tablenames(), get.tablefields(),

Hi R users, I have a question about adding a column for water year. The dataframe has the structure below. But the wyear column just shows one year. Could anyone help me with this problem? Thanks. DF year month day time flow 1972 1 1 1972-01-01 5 1972 1 2 1972-01-02 5.5 1972 1 3 1972-01-03 6 ... 1985 12

I understand how R treats NAs but in the situation below it would be nice to have a na.skip argument to paste so it does not convert the NAs to "NA"s and simply skips those elements of the vector for pasting. > x [1] "2.13" "2.3" NA NA "2.83" NA > paste(x, "0", sep="") [1] "2.130" "2.30"

Hi I have a 3 x 2 contingency table: 10 20 30 40 50 60 I want to update the frequencies to new marginal totals: 100 130 40 80 110 I want to use the ipf (iterative proportional fitting) function which is apparently in the cat package. Can somebody please advice me how to input this data and invoke ipf in R to obtain an updated contingency table? Thanks. By the way I am quite new to R. -- Dr

i am new to R,so i post here to ask you how to learn R quickly? is there some usefull materials about using R. ps:though the manual is a good materials,but it is not the best for a newbie,i think. thank you !

Hi everybody: I need to get the names of the arguments in an object of class "expression". I've got the following expression: > x <- expression(rho * cos(omega)) Is there any function or procedure that returns the names of the arguments (in the example: "rho" and "omega")? I tried a rough approach implemented in the function expr.args() shown below. As

sorry, my previous message got sent too early I think the macro should look something like this: #define ASSERT_STRM(cond,expr) \ do { if (cond) { std::cerr << expr << std::end; assertion_trap (); } } while (false) On Tue, Jul 26, 2011 at 7:57 PM, Nathan Jeffords <blunted2night at gmail.com>wrote: > wrapping the macro's body in: > > do { ... } while

Hi everyone, When dealing with errors, sometimes I want to run a bunch of code when an error occurs. For now I usually use a structure such as: res <- tryCatch(expr, error = function(cond) cond) # or try(expr) if (inherits(res, ?error?)) # or inherits(res, ?try-error?) # a bunch of code I though it would be useful to have a function that does this naturally, so I came up with the attached

Hi Emil, First, thanks for the response. As you mentioned, a lot of times tryCatch does the work, as you can return a value. However, sometimes it is useful to assign several variables when an error occurs. You could do it with <<-, but I prefer to reduce it's usage unless completely necessary. I guess that the attachment was missed in the moderation. Here it is the function:

I need to write an if/then statement saying something along the lines of: if (VALUE is in list) {... How do I write that in R's language. Thanks! -- View this message in context: http://r.789695.n4.nabble.com/If-then-statement-if-in-a-list-then-tp4638346.html Sent from the R help mailing list archive at Nabble.com.

I put a copy of R 1.8.1 for Windows on our FTP site at: ftp://ftp.odot.state.or.us/outgoing/Test/. It should be there for a few days before it gets deleted. Benjamin Stabler Transportation Planning Analysis Unit Oregon Department of Transportation 555 13th Street NE, Suite 2 Salem, OR 97301 Ph: 503-986-4104 -----Original Message----- From: Peter Wilkinson [mailto:pwilkinson at videotron.ca]