similar to: Doing operations by grouping variable

I would like to use POSIX classes to store dates and extract components of dates. Following the example in Spector ("Data Manipulation in R"), I create a date > mydate = as. POSIXlt('2005-4-19 7:01:00') I then successfully extract the day with the command > mydate$day [1] 19 But when I try to extract the month > mydate$mon [1] 3 it returns the wrong month. And

I have a data set similar to this: P1id Veg1 Veg2 AreaPoly2 P2ID 1 p p 1 1 1 p p 1.5 2 2 p p 2 3 2 p h 3.5 4 For each group of "Poly1id" records, I wish to output (subset) the record which has largest "AreaPoly2" value, but only if

I wish to create a multipanel plot (map) from several datasets ("d" and "q" in the example below). I can condition the main xyplot statement on the "site" variable, but I don't know how to pass a conditioning variable to panel.xyplot plot so that the x-y coordinates from dataset q are only plotted at the appropriate site. library(lattice) d <-

I have a moderately complex graph with three panels. There are data points plotted, and fitted lines are added using a panel function, which includes "with(alt.data[[which.packet()[1]]]" statements. It all graphs out beautifully, but none of the usual tricks to get the proper legend to plot are working, i.e., using auto.key, key, etc. One message I keep getting is Error in

I wish to identify groups representing different treatments, but to plot them and do a regression using a continuous variable ("cover") ignoring the groupings. d$year <- NA d$year <-c(rep(2007,12), rep(2008,12)) d$treatment <- c(rep("A",4),rep("B",4),rep("C",4), rep("A",4), rep("B",4), rep("C",4)) d$cover <-

I have a list that is made of lists of varying length. I wish to create a new vector that contains the last element of each list. So far I have used sapply to determine the length of each list, but I'm stymied at the part where I index the list to make a new vector containing only the last item of each list mylist =

How can I eliminate the border drawn by default around a wireframe plot? I've tried using border=NA and box=FALSE to no avail. Scott Waichler Pacific Northwest National Laboratory scott.waichler at pnl.gov

I would like to eliminate the outer box around a lattice wireframe graph, but the usual recommended solution, which is to assign a color of 'transparent' to the axis.line parameter, eliminates ticks if the 'arrows=F' command is used, as shown in the following example: test = data.frame(expand.grid(c(1:10), c(1:10))) z = test[,1] + test[,2] test = cbind(test, z) names(test) =

Friends: I wish to overlay data points on a contour graph. The following example produces a nice contour plot, but I have not mastered the concept of using panel functions to modify plots. Can someone show me how to overlay the data points (given after contour plot statement) on the contourplot? --Seth model <- function(a,b,c,X1,X2) # provide model function for contour

I wish to display a single-panel Lattice figure with grouped data and fitted regression lines. I don't seem to be able to get the individual regression lines to display, e.g.; d <- data.frame(q = rep(1:6, each=10), cc = rep(seq(10,100, 10),6)) # create data frame with group identifier 'q', independent variable cc d$ba = d$q*0.1*d$cc + 5*rnorm(nrow(d))

Thanks to all that replied. I had just looked through the httr code and sure enough for a .csv mime time it calls readr::read_csv(). The httr::content docs suggest not using automatic parsing in a package, rather to determine mime type and parse yourself and Ben's suggestion also works if I do: junk <- readr::read_csv(r1$content, col_types = cols()) Perfect. Using httr rather than

Ahoy! That's a message generated by the readr::read_table() function (or it's friends). You can suppress it a number of ways, but this should work as httr::content() will pass through arguments, like col_types = cols(), to the file reader. junk <- httr::content(r1, col_types = cols()) See more here... https://blog.rstudio.com/2016/08/05/readr-1-0-0/

I would like to remove the outermost box from my wireframe plots -- this is the box that is automatically generated, and is not the inner cube that frames the data. There was a thread on this 4 yrs ago but none of the fixes work (e.g., grid.newpage(), grid.lines(gp = gpar(col = NA)) or par.box=list(col=1),col=NA. These just make the data or the cube disappear. Has anyone solved this issue?

I'm working on a contourplot( ) graph, the subject of several previous posts to this list. The contours express probabilities from 0 - 1, but the key that is automatically generated by contourplot pads the probability scale with values that are impossible (i.e, range goes from -0.2 to 1.2), which will be confusing to those who view the plot. How can I get the scale to just run from 0 - 1?

Hi, It's a reasonable question. The answer is that it actually is included, but there are many instances across packages where multiple functions are documented on a single help page. The following brings up such a page... (for XML_3.98-1.9) > library(XML) > ?newXMLNode You can see the same on line... https://www.rdocumentation.org/packages/XML/versions/3.98-1.9/topics/newXMLDoc

Just to clarify and hopefully catch the attention of the maintainer: The newXMLNode function is not mentioned in: https://cran.r-project.org/web/packages/XML/XML.pdf which supposedly describes all functions in the package. Stephen From: Ben Tupper [mailto:btupper at bigelow.org] Sent: Thursday, March 22, 2018 10:40 AM To: Bond, Stephen Cc: r-help Subject: Re: [R] how to add a child to a

Hi, If you are using roxygen-style function documentation then why not use devtools::document()? Ben > On Dec 16, 2017, at 9:00 AM, Erin Hodgess <erinm.hodgess at gmail.com> wrote: > > Hello everyone! > > I'm in the process of writing a package, and I'm using the lovely "R > Package" book as a guideline. > > However, in the midst of my

Big thanks. newXMLNode works great. Wonder why it is not included in the documentation. There is newXMLDoc and newXMLNamespace, but no mention of newXMLNode. Stephen From: Ben Tupper [mailto:btupper at bigelow.org] Sent: Wednesday, March 21, 2018 6:18 PM To: Bond, Stephen Cc: r-help Subject: Re: [R] how to add a child to a child in XML Hi, XML doesn't use the `$` to access child nodes.

Indeed, Ben, but the question was something more like it is not a Dependency, just Suggested, so why the error... John: If you read the Introduction to the 'raster' package vignette, it indicates that some input formats are supported within the raster package and some rely on other packages. Clearly the attempt to read a TIFF was an example of the latter. Had you used a different input

Dear list, I am trying to download a text file from an ftp site using download.file(). I used the following code: url <- "ftp://ftp.wcc.nrcs.usda.gov/data/snow/snow_course/table/history/idaho/13e19.txt" dest <- "c:/test/downloadtest.txt" download.file(url, dest) I get this error message, indicating that R is unable to open the connection: trying URL