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I have a dataframe (x) and I'm plotting the 5th column vs the index. I also have a vector (v) with a few select points that I want to emphasize with a dot for those points > head(x) period AP EU LA NA 1 Jan 2007 0.18 0.45 0.19 3.19 2 Feb 2007 0.14 0.48 0.36 3.55 3 Mar 2007 0.14 0.42 0.46 2.61 4 Apr 2007 0.24 0.73 0.32 4.32 5 May 2007 0.19 0.60 0.32 4.40 6 Jun 2007 0.14 0.38

Seems like this should be easy but I'm struggling a bit. How do I rearrange a data frame to go from the first one to the second shown below ? State Date lbs TX 200701 400 TX 200702 650 TX 200703 950 TX 200704 1000 FL 200701 200 FL 200702 300 FL 200703 500 FL 200704 333 NJ 200701 409 NJ 200702 308 NJ 200703 300 NJ 200704 800 Date TX FL NJ 200701 400 200 409 200702 650

Statement 9 using sapply does not seem to give the correct answer (or at least to me). Yet I do what I think is the same thing with statement 11 and I get the answer I'm looking for. 9 : s <-sapply(unlist(v[c(1:length(v))]), max) 11: for(i in 1 :length(v)) v1[i] <- max(unlist(v[i])) Shouldn't I get the same answer ? library(XML) rm(list=ls()) url <-

I am reading some data into R from an Excel spreadsheet using read.csv. Some of the original data that comes into column 1 from the spreadsheet is text that says NA. The NA stands for north america. As it comes in, R converts the NA over to <NA>. What is the cleanest way to change the <NA> values to something else. In other words, get rid of the brackets ? Maybe convert <NA>

I'd like to use vectorization to take a 4 point moving window on standard deviation on the close column and create another variable (st.dev) in the dataframe. Here's the dataframe head(xyz) Date Close 1 2011-01-28 56.42 2 2011-01-27 57.37 3 2011-01-26 56.48 4 2011-01-25 56.39 5 2011-01-24 55.74 6 2011-01-21 55.46 So the first 3 elements to the new st.dev column would be zero

Can't seem to get the code below working. It gets stuck on line 24 inside the function hm; comments show the line in question. The function hm is called by sapply and is at the bottom of the code. Other stuff above line 24 works correctly including the first couple of lines of the function hm. Should I be using a different apply function or am I doing something wrong with xmlTreeParse ?

I have the following lines of code: ind <- rollapply(GSPC, 200, mean) signal <- ifelse(diff(ind, 5) > 0 , 1 , -1) signal[is.na(signal)] <- 0 I never get a value of -1 for signal even though I know diff(ind , 5) is less than zero frequently. It looks like when diff(ind , 5) is less than zero, signal gets set to 0 instead of - 1. Any ideas why ? Here's some information on ind and

Just starting to learn R so excuse me if this is a simple question. I'm wondering how I get the percent difference in sequential values in one column of a dataframe. If I had a dataframe and one of the columns was "value", how would I go about calculating (v2-v1)/v1 ....(v3-v2)/v2 ....(v4-v3)/v3 ...etc ? -- View this message in context:

I'm running Linux Ubuntu and tried to update my packages using the update.package() command. It appeared to download the updates ok but I got the following message: The downloaded packages are in ?/tmp/RtmpFM82Ry/downloaded_packages? Warning in install.packages(update[instlib == l, "Package"], l, contriburl = contriburl, : 'lib = "/usr/lib/R/site-library"' is

I am calling the uniroot function from inside another function using these lines (last two lines of the function) : d <- uniroot(k, c(.001, 250), tol=.05) return(d$root) The problem is that on occasion there's a problem with the values I'm passing to uniroot. In those instances uniroot stops and sends a message that it can't calculate the root because f.upper * f.lower is greater

Basic question but still learning .... How do I plot two lines (f$equity and f$bh.equity) on one of the three graphs under mfrow ? I tried putting brackets around the first plot and lines command but that didn't work. par(mfrow=c(3,1)) {plot(f$Date,f$equity, col="blue", type="l", main="equity") lines(f$bh.equity, col="gray")} plot(f$Date,f$indicator,

I used screen scraping to extract some information and put it into a table called tbl. Now I want to modify the table a bit so the data can be more useful. Here's the code I used: library(XML) rm(list=ls()) url <- "http://webapp.montcopa.org/sherreal/salelist.asp?saledate=05/25/2011" tbl <-data.frame(readHTMLTable(url))[2:405, c(3,5,6,8,9)] names(tbl) <-

I have a data frame x that came from read.csv. It seemed to read in ok but then I tried doing some plotting of the values and ran into difficulties. The plot command seems to be plotting factors instead of the values. How do I get rid of these factors ? The plot command I use is : plot (x$dat, x$TX, type='l'). I also tried ...plot(x$dat, levels(x$TX), type='l) but got an error :

I have a data frame called test shown below that i would like to summarize in a particular way : I want to show the column sums (columns y ,f) grouped by country (column e1). However, I'm looking for the data to be split according to column e2. In other words, two tables of sum by country. One table for "con" and one table for "std" shown in column e2. Finally at the

I'm trying to install the rdatamarket package. I did an install.packages('rdatamarket') command but got an error about half way through the install as follows: * installing *source* package ?RCurl? ... checking for curl-config... no Cannot find curl-config ERROR: configuration failed for package ?RCurl? The install continued after the error but looks like it was completed. I'm

How do I change the name of one column in a data frame ? Suppose I have a data frame x with 5 columns. If the names were date, col1, col2, col3, col4 and I wanted to simply change the name of date, what would the command be ? I tried the following and it didn't seem to work : names(x[1]) <- "newname" Thanks in advance for the comments -- View this message in context:

What am I doing wrong here ? And what's the right way to calculate the log differences in a column in a df ? # first 3 rows of 5000 rows y[1:3,] Date Open High Low Close 1 1983-03-30 29.96 30.51 29.96 30.35 2 1983-03-31 30.35 30.55 30.20 30.24 3 1983-04-04 30.25 30.65 30.24 30.39 #equation in question ...why is this giving zeros ? y1 <- 100*log(y[,5]/(lag(y[,5],1))) # first 10

Having a hard time understanding the help files for tryCatch. Looking for a little help with the following statement which sits inside a for loop zest[i] <- tryCatch(sapply(getNodeSet(zdoc, "//zestimate/amount"), xmlValue), error=function() zest[i] <-"NA") zest is a numeric vector If the sapply statement evaluates to an error, I'd like to set the value of zest[i]

Just when I think I'm starting to learn .... Statement z1 works, statement z doesn't. Why doesn't z work and what do I do to fix it ? Clearly the problem is with the first NA, but I would think it's handled through the loop vectorization. y1 <- rnorm(20, 0, .013) y1 [1] -0.0068630836 -0.0101106230 -0.0169663344 -0.0066314769 0.0075063818 [6] -0.0033548024 0.0015647863

I tried to update my packages using update.packages() I got the following message: The downloaded packages are in ?/tmp/RtmpyDYdTX/downloaded_packages? Warning in install.packages(update[instlib == l, "Package"], l, contriburl = contriburl, : 'lib = "/usr/lib/R/library"' is not writable Error in install.packages(update[instlib == l, "Package"], l,