similar to: update.packages() after updating R version

The bio.infer package contains a data frame /usr/lib/R/library/bio.infer/data/itis.ttable.rda that needs to be modified. After loading the bio.infer package and attaching the data frame with the data() function, I wrote the data frame to a text file. After adding another row to the data frame I applied read.table() to create a data frame, but it's in my pwd, not the R library data

I have a reshaped data frame with value column headings concatenated from two column headings in the melted data frame. I want to change all 56 headings in a single command, but 'names' allows me to change only one at a time. In Hadley's 2007 article on reshape in the Journal of Statistical Software he mentions a 'rename' function, but I cannot find that. Is there a way to

I have a data frame called chemdata with this structure: > str(chemdata) 'data.frame': 14886 obs. of 4 variables: $ site : Factor w/ 148 levels "BC-0.5","BC-1",..: 104 145 126 115 114 128 124 2 3 3 ... $ sampdate: Date, format: "1996-12-27" "1996-08-22" ... $ param : Factor w/ 8 levels "As","Ca","Cl",..:

I need to understand how and why dcast() adds NAs to a data frame that contained no missing values. The database table of chemical concentrations has all missing values removed because they cannot contribute to data analyses. The structure of the R data frame of these data have no NA values, and neither does the data frame resulting from applying the reshape2 melt() function to it. However,

One of many scripts to produce 4 lattice plots on one page keeps throwing an error. I've tried manipulating the file to eliminate the error, but have not been able to do so. The error is: > source('bicarb.R') Error in source("bicarb.R") : bicarb.R:15:1: unexpected symbol 14: 15: hco33 ^ The 'h' is in column 0 so the caret would be column -1, but it's

With multiple panels in a lattice trellis plot the sequence is, for example, 1, 10, 11, 12, 2, 3, 4. I want the sequence to be 1, 2, 3, 4, 10, 11, 12. Reading ?strip.default and the appropriate section in the Lattice book I'm not seeing how to specify the 'human' numeric order rather than the computer numeric order. A pointer will be appreciated. TIA, Rich

Hi Albrecht, I am forwarding your reply to the full group. It's been a while since I did this and I don't remember the details. Maybe someone else can comment. (I am a bit busy at the moment.) If no one supplies the information in a few days I will try to take a look. In the meantime you can start your reading on-line. :-) Regards, Eric Dear Eric, I downloaded the material from

I've looked at the lattice book and the 'R Graphics Cookbook' without seeing how to change the labels along the x axis for groups in a box plot, specifically cenbox(). The attached example has a main and axes labels with default group labels. Please point me to a reference on how I can change 'FALSE' and 'TRUE' to something more easily understood by viewers. TIA,

I read in ?na.omit that it returns the object with incomplete cases removed. I interpret this to mean that any zoo object row where any column shows 'NA' will be removed from the data set. That's not what I need, since the 'NA' represents information in my context. However, what I would like to do is eliminate the rows where every column is 'NA'. When I aggregate

I have water chemistry data with censored values (i.e., those less than reporting levels) in a data frame with a narrow (i.e., database table) format. The structure is: $ site : Factor w/ 64 levels "D-1","D-2","D-3",..: 1 1 1 1 1 1 1 1 ... $ sampdate: Date, format: "2007-12-12" "2007-12-12" ... $ preeq0 : logi TRUE TRUE TRUE TRUE TRUE

Hello R user, I have a data set from a longitudinal study ( sample below) where subjects are followed over time. Second column (status) contains info about if subject is dead or still in the study and third column is time measured in the week. Here is what I need: if status is not dead or unknown take the last week, if status is dead or unknown I need to have corresponding week. Desired resulst:

I need to generate 6 x-y scatter plots (lattice xyplot) for each of 11 data frames. I'm sure the tedium of doing these one at a time can be avoided by writing a script that uses nested for loops or the apply() function. My Web search has not provided me with a tutorial on R programming that will introduce me to the language and allow me to write such a script. Please provide pointers to

All but one of the summaries of multiple linear regressions in this analysis set present the residuals by min, 1Q, median, 3Q, and max. Example: lm(formula = TDS ~ Cond + Ca + Cl + Mg + Na + SO4, data = snow.cast) Residuals: Min 1Q Median 3Q Max -277.351 -32.551 -2.621 40.812 245.272 The one that doesn't has only a small number of rows (23) and presents the

I just upgraded from 2.14 to 2.15 and have run into an issue upgrading libraries that I've not had in previous version upgrades. For example, trying to install reshape2 for 2.15 throws errors and I don't see what to change to over come the problem: > install.packages("reshape2") Installing package(s) into ?/home/rshepard/R/i486-slackware-linux-gnu-library/2.15? (as ?lib? is

Ah.... LOD's, typically LLOD's ("lower limits of detection"). Disclaimer: I am *NOT* in any sense an expert on such matters. What follows are just some comments based on my personal experience. Please filter accordingly. Also, while I kept it on list as Martin suggested it might be useful to do so, most folks probably can safely ignore the rant that follows as off topic and not

One set of data has censored (less-than detection limits) water chemistry concentrations for 80-100% of all observations. My initial trial-and-error attempts to apply the cenboxplot() method suggests that it has an upper limit to the percentage of censored observations. I do not see this limit in Dennis Helsel's second edition. Has anyone experience plotting censored data and can provide

While reading ?subset I'm referred to learn about dropvalues() as a following operation. Yet, when I issue ?dropvalue I see, "No documentation for '?dropvalues' in specified packages and libraries:". How do I identify the library/package that contains a specific function such as, in this case, dropvalues()? Rich

I just upgraded from 2.15.2 to 2.15.3 on our Slackware systems and see the following when testing that the new version properly loads: "The following object(s) are masked from 'package:stats': cor "The following object(s) are masked from 'package:base': as.Date, as.Date.numeric" What, exactly, does this mean? Also, I assume that if I see no errors

I've a data frame with this structure: 'data.frame': 1987 obs. of 11 variables: $ site : Factor w/ 24 levels "B(W)","BC-1",..: 1 1 2 2 2 1 1 1 ... $ sampdate : Date, format: "2000-07-18" "2000-07-18" ... $ tclass : Factor w/ 8 levels "Annelida","Arachnida",..: 1 5 5 5 5 ... $ torder : Factor

A statistical question, not specific to R. I'm asking for a pointer for a source of definitive descriptions of what types of data are best summarized by the arithmetic, geometric, and harmonic means. As an aquatic ecologist I see regulators apply the geometric mean to geochemical concentrations rather than using the arithmetic mean. I want to know whether the geometric mean of a set of