similar to: Pros and Cons of R

R has very good GUI packages that I have used - R Commander RCmdr and Rattle rattle . Since I work on multiple packages with constraints of time, I almost always use the GUI rather go through the intricacies of command line . The log of these GUIs shows the relevant R command that was used, so you can actually learn the language also. I have written about the ease of learning R , if you begin

Hi, First of all thanks for all the answers .... all were very informative and helped me shape a better presentation. Although i received lots of emails saying that installation under Linux / Unix is easy .... still emails asking for help in installing R itself, or external packages and such crop more often than not on the list and for this reason i pressumed it is harder to install under Linux

Hi, I am getting some strange results using round - it seems that it depends if the number before the decimal point is odd or even .... For example: > round(1.5)[1] 2> round(2.5)[1] 2 While i would expect that round(2.5) be 3 and not 2. Do you have any explanation for that? I really appreciate your input, Monica

Hi everyone, I have a vector of strings, each string made up by different number of words. I want to get a new vector which has only the first word of each string in the first vector. I came up with this: str <- c('aaa bbb', 'cc', 'd eee aa', 'mmm o n') str1 <- rep(1, length(str)) for (i in 1:length(str)) { str1[i] <- strsplit(str, "

Hi everyone, ? I am trying to get a point of intersection between a polyline and a straight line ?.. and get the x and y coordinates of this point. For exemplification consider this: ? ? set.seed(123) ? k1 <-rnorm(100, mean=1.77, sd=3.33) ?k1 <- sort(k1) q1 <- rnorm(100, mean=2.37, sd=0.74) q1 <- sort(q1, decreasing = TRUE) plot(k1, q1, xlim <- c((min(k1)-5),

Hi, I am using an if else statement inside a function ?. If I use that function I have no problems ?. If I use the function with the if else statement inside a second function I get the following waring: Warning message: In if (pval == 0) p_value <- "< 2.2e-16" else p_value <- pval : the condition has length> 1 and only the first element will be used Using the second

Hi everybody, I have a vector of characters and i would like to extract certain parts. My vector is named metr_list: [1] "F:/Naval_Live_Oaks/2005/data//BE.tif" [2] "F:/Naval_Live_Oaks/2005/data//CH.tif" [3] "F:/Naval_Live_Oaks/2005/data//CRR.tif" [4] "F:/Naval_Live_Oaks/2005/data//HOME.tif" And i would like to extract BE, CH, CRR, and HOME in a

Hi everybody, I have a vector of characters and i would like to extract certain parts. My vector is named metr_list: [1] "F:/Naval_Live_Oaks/2005/data//BE.tif" [2] "F:/Naval_Live_Oaks/2005/data//CH.tif" [3] "F:/Naval_Live_Oaks/2005/data//CRR.tif" [4] "F:/Naval_Live_Oaks/2005/data//HOME.tif" And i would like to extract BE, CH, CRR, and HOME in a

Hi list, I have a question about 'plot'. I am trying to plot values registered every month - or every other month. If i build a data.frame called mydata like this (as an example) jan 3 1 7 mar 2 4 2 may 1 3 2 jul 3 7 4 sep 5 2 3 nov 3 1 5 and use the command line: plot(mydata[c(1,3)]) I get a graph that has on the x axis my months in alphabetical

Hi, I am trying to get percentages in a more elegant way. I have a data.frame with locations and values (counts) of species at that location. Each location is repeated for each species i have values for and i would like to get percentages of each species at that location. I am not sure if i am clear in my explanations so i will paste my code below: ##################### > x locat val 1

Hi, I have to recognize that i don't fully understand the aggregate function, but i think it should help me with what i want to do. xveg is a data.frame with location, species, and total for the species. Each location is repeated, once for every species present at that location. For each location i want to find out which species has the maximum total ... so i've tried different ways to

Dear list, I have to compare two digital elevation models in raster format (geotiff). I then have to calculate the differences in altitude for each cell and make some statistics (basic as mean, median, std, range but also more "advanced" as RMSE) on that. I do not know very much how to proceed: 1) is it possible to import the geotiff in R? If so with which package? if not which is the

Hi, I am sure there is a reason but ...... why larger decimal numbers get rounded to the nearest integer? Example: a <- 3308000.5 a [1] 3308001 I would like my numbers to be decimals .... since they do represent coordinates and i don't want them rounded .... how can i keep them as they are? Thanks, Monica _________________________________________________________________

Hi, I would like to use the function "extract" from package raster and i get the following error: m01e <- extract(marsh01, p) Error: could not find function "extract" marsh01 is a raster object and p is an intersectExtent object that is not null. The package is installed and loaded, i use a Windows machine 64 bit and R x64 2.11.0. Do i really need to update my R to use

Hi, I have a set of irregular time series and i want to produce a simple plot, with dates on x axis and attribute value of y axis. This is simple enough but my x axis is divided automatically by ticks every 5 years. I would like to have a tick every year at January 1st. I am not sure how i can do that - i end up with something very close to what i want, but it is clunky and not very correct. I

Hello list, I am wondering if a joining "one-to-many" can be done a little bit easier. I tried merge function but I was not able to do it, so I end up using for and if. Suppose you have a table with locations, each location repeated several times, and some attributes at that location. The second table has the same locations, but only once with a different set of attributes. I would

Hi, I hope someone knows the answer to this or has a real good reference about it (I am using Legendre & Legendre, Numerical Ecology, 1998).... My data is a data.frame with locations as rows and vegetation assemblages / species as columns. I've done a PCA, a correspondance analysis (CA) using ca in ca package and a detrended correspondance analysis (DCA) using decorana from vegan package.

Hi, I have a graph and I would like to write some values inside the legend that were saved in a variable. Please revise the code below in which I've wrote 2 different legends, but I am not happy with either of them. What I want is a legend with tile "Legend" and underneath a line with a name and a value like that: value = 2. #Code begin: # ------------------- a = 2 # result of a

Hi, I have 4 huge tables on which i want to do a PCA analysis and a kmean clustering. If i run each table individually i have no problems, but if i want to run it in a for loop i exceed the memory alocation after the second table, even if i save the results as a csv table and i clean up all the big objects with rm command. To me it seems that even if i don't have the objects anymore, the

Hi, I’ve written some code to obtain a confusion matrix when the true classification and the predicted classification are known. Suppose true classification is called “tr” and predicted classification is “pr”. I have 4 classes in tr, but only 3 classes out of 4 are predicted in “pr”. Following is my code, but looks quite “clunky” to me. I wonder if you have any suggestions to improve it.