similar to: unique, but keep LAST occurence

I was just looking for an easy way to convert between COM datetime and chron datetime (both ways.) I found examples on the list, but they involved origin. Does anyone have functions for converting COM datetime <-> chron datetimethat work "safely"? David L. Reiner > -----Original Message----- > From: Gabor Grothendieck [mailto:ggrothendieck@gmail.com] >

Could someone please suggest a more clever solution to the following problem than my loop below? Given X a 2xN matrix X, and I a k-subset of N, Generate the (2^k)xN matrix Y with columns not in I all zero and the other columns with all choices of an entry from the first or second row of X. For example, with X <- matrix(1:8, nrow=2) I <- c(1,3) X is 1 3 5 7 2 4 6 8 and Y should be 1 0 5

I'm using v 1.9.1 under Windoz XP. Can I do the equivalent of "ls -l" on my R objects? R's "ls()" lists only the names. Thanks! David L. Reiner Rho Trading 440 S. LaSalle St -- Suite 620 Chicago IL 60605 312-362-4963 (voice) 312-362-4941 (fax) [[alternative HTML version deleted]]

I'm trying to use/modify some code I found (at Omegahat, but I've seem similar usage elsewhere.) It contains the lines: if(any(origin(chronDate)!=orig)) origin(chronDate) <- orig Let's say: > require("chron") [1] TRUE > chronDate <- chron("11/15/2005", format="m/d/y", origin.=c(12,31,1899)) > orig <- c(month=12, day=31,

I'm having trouble with the standard deviation distribution as shown on http://mathworld.wolfram.com/StandardDeviationDistribution.html . (Eric Weisstein references Kenney and Keeping 1951, which I can't check.) I believe the graphs they show, but when I code the function in R, according to the listed formula, I get very different graphs. Would someone please point out my error or tell

This is a windows-specific question. After generating a plot, I can print from scripts or the command line with > dev.print(win.print,printer="local windows printer name") I would like to print in landscape mode. From the menus, I can accomplish this by changing the properties of the printer before clicking "print". However, I tried adding

Could someone please tell me what I did wrong to create this message or what I should do to correct this problem? I downloaded 2.1.0 Windows binary and installed into C:/R/rw2010, using the installer. I ran md5check.exe in C:/R/rw2010/bin/ and got "No errors." The problem is this: When I start up Rgui.exe from its shortcut (target= C:\R\rw2010\bin\Rgui.exe --save -sdi, Start in

Could someone please help me by giving me a reference to how one computes standard errors for the coefficients in an orthogonal linear regression, or perhaps someone has some R code? (I would accept a derivation or formula, but as a former teacher, I know how that can rankle.) I tried to imitate what's done in the code for lm() but went astray somewhere and got nonsense. (This type of

pretty() works well for numbers and axTicks() can help for potting log axes, but has anyone written a pretty for chron objects (or other date or date-time classes)? It would have natural units of years, months, .., days, hours, (minutes?), and it would choose the appropriate unit based on the date(time) range. I have searched the archives and documentation to no avail. (I wrote one of these back

I'd like to insert (for example) the current datetime into a comment so it goes into the history. I can of course cut and paste the results of date() into a comment line, but it would be easier and more powerful to be able to type something like > hstamp() and have it go into the history. More generally, I would like to put any expression to be evaluated into this function. For

R-help Is there any way to specify the color of grid lines in a simple plot? par(color.tick.marks=c("grey")) plot(rnorm(10),tck=1) Thank you

But that doesn't put the result into the history buffer, to be written to a file only later when I savehistory(filename). Bert Gunter also suggested ?capture.output and ?textConnection, but I cannot see how to get text into the history buffer as comments, but with evaluated expressions (values). I know how to use paste, sink, write, etc. but nothing that I can see inserts into the history

Hi I have been wondering if there one can speed up calculating small powers of numbers such as x^8 using multiplication. In addition, one can be a bit clever and calculate x^8 using only 3 multiplies. look at this: > f1 <- function(x){x*x*x*x*x*x*x*x} > f2 <- function(x){x^8} > f3 <- function(x){x2 <- x*x;x4 <- x2*x2;return(x4*x4)} [so f1() and f2() and f3() are

Hello, R gives us the correlation functions cor(). (Many thanks ;-)) Does it also exist a "moving correlation" coefficient ? (like the moving average). If not, could someone give me some infos or link on how to practically implement such a function in R. (I did search for "moving correlation" on the R homepage but didn't find anything.) Thank you. Vincent

I'm having trouble reshaping a data.frame from long to wide. (I think that's the right terminology; feel free to educate me.) I've looked at the reshape function and package and plyr package, but I can't quite figure out how to do this after a dozen variations. I have a data.frame with more levels than this, but similar to: > tst K1 K2 K3 V1 V2 V3 1 10 D a 0.08 99

I'm getting warnings when I plot a zoo object: > dts <- chron(rep("2007-09-10", 5), paste("00:0", 0:4, ":00", sep=""), c("y-m-d", "h:m:s")) > dat.zoo <- zoo(1:5, dts) > plot(dat.zoo) Warning messages: 1: In v[[perm[1]]] : partial match of 'm' to 'month' 2: In v[[perm[2]]] : partial match of 'd'

I just noticed a change in the behavior of list.files from 2.6.1pat to 2.7.0 (I noticed it in 2.8.1 and traced back.) Previously, if the directory ended with a slash, and full.names=TRUE, the names returned had a single slash at the end of the directory, but now there are two. I noticed since I was getting a list of certain files and then grepping in the list for a full name formed with a

sqldf is an R package for running SQL select statements on one or more R data frames. It is optimized for convenience making it useful for ad hoc queries against R data frames. Given an SQL select statement whose tables are the names of R data frames it: - sets up the database (by default it transparently sets up an in memory SQLite database using RSQLite; however, MySQL via RMySQL, can be

sqldf is an R package for running SQL select statements on one or more R data frames. It is optimized for convenience making it useful for ad hoc queries against R data frames. Given an SQL select statement whose tables are the names of R data frames it: - sets up the database (by default it transparently sets up an in memory SQLite database using RSQLite; however, MySQL via RMySQL, can be

I have a data.frame which I believe is melted already and am having trouble casting it to 'wide' format. It looks something like > (x <- data.frame(ticker=c(rep("A",5),rep("B",6)), date=c(1:5, 1:6), value=c(NA,100*exp(rnorm(10,0,.1))))) > cast(x, date ~ ticker) # this does what I want with toy data But when I use my real data frame >