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Dear R-list, Is there any way I can extract part or whole column name from two variables and combine them? Not values, but column names. For example, I have data set with 70 variables. The column names are "Alfalfa", "Corn","Soybean",..."Sunflower". After I combine the two variable (say Alfalfa and Corn), I want to rename it as "AlfCor" or

Hello, My program calculates several variables at each iteration and some of them are integers and the rest are numeric. When I save them into a matrix, all of them are of numeric type, of course. I'm trying to find a way to save time/memory of my program and I was thinking that it might help to force some variables to be of integer type and the other columns numeric type. But when I

Dear R-Help List, I have a question about data manipulation. I tried to make code myself but too much for me. I would greatly appreciate your help. I have data set consisting of site (from 1 to N1) and distance and there are several variables (1 to N2) collected from each sampling site. I am interested in looking at cumulative sums of each variable based on site and distance like below. Can

Dear R Lists, Can anyone help me add site IDs (site: 1~50) directly to my xyplot. I have 50 sites and collected observations from the sites at 13 different time points. I want to look at the change of my observations in each site. I was able to make a graph using xyplot, however, I can't find how to add site IDs within the graph not adding them in the legend. Overall, I would like to be able

I need to generate good quality of random numbers from univariate normal distribution for further transformation. I tried rnorm in R but it was not good sometimes. Someone said C++ standard library or Fortran's built-in functions for that are good. I found that there is double norm_rand() in R-extension. Does this function, norm_rand() use the same algorithm as rnorm in R or something similar

Hello all, I'm trying to have C called by R. I wrote C codes that worked perfectly fine with R-2.6.0 in windows system ( using R tools). I had to change to SuSE Linux (this system has 3.2 GHz Intel Xeon processors and 4 GB of RAM), the C codes were compiled okay but when it was called to R-2.6.2, I got error mesage : ***caught segfault*** address 0x1df5000, cause 'memory not

Hello I wrote a bootstrap program in C language that is called and run by R. When I tried it, it is slow and I'm trying to write and run the whole thing in C. But I cannot use handy functions in R and need to figure out how to write those functions by myself. Is there any way that I can get the actual codes that implement functions in R so that I can translate them into other languages? For

Hello, I'm having trouble in using "assign(paste ..." command . I could create several dataframes following trinomial distribution using it but it could not be used to check their row means of the created dataframe. For example, the following works: probTrt=matrix(0,4,3); probTrt; #malf, death, normal probTrt[1,]=c(0.064,0.119,0.817);#for Trt 1 probTrt[2,]=c(0.053,0.125,0.823);#for

Can anyone help me with lbfgsb (function for optimization)? It takes the following parameters: void lbfgsb (int n, int lmm, double *x, double *lower, double *upper, int *nbd, double *Fmin, optimfn fn, optimgr gr, int *fail, void *ex, double factr, double pgtol, int *fncount, int *grcount, int maxit, char *msg, int trace, int nREPORT); What do I put for parameter ex (11th parameter)? I looked at

The previous mail I wrote was bounced for some reason and I'm writing it again... I have used Rtools in windows to call C from R but my computer does not have enough memory for my current project. So I'm trying to use Rtools in the high performance computer at my school. The guy who handles the HPC says it's Unix and I have three questions: 1. I found from the web that Unix has

Hello list, I found that system.time works correctly when I used "<-" to assign a value to a variable but when I happened to use "=" instead of "<-", R gave an error message: "Error in system.time(your argument here...)". It happened with a few functions I tried. Is this a bug or is there any circumstances that "=" cannot be used for

I have a huge matrix and need to delete certain rows. What I need to do is: 1.In each row, calculate the sum of jth column and (J+2)th column 2. If the sum is greater than 2 then that row needs to be deleted. I have a sample matrix and my codes here. It does remove some rows but when it does, it skips the next row and each time it deletes a row, the dimension changes so it gets out of bound. I

Hi list, To call C, I used to use R-extension in windows but I'm moving to unix system because my PC doesn't have enough memory. My C codes requires to include the following header files: #include <stdlib.h> #include <R.h> #include <Rdefines.h> #include <Rmath.h> #include <R_ext/Applic.h> #include <R_ext/PrtUtil.h> In windows, I had no problem with it

Hello, I'm having two similar problems with for loop and I would appreciate any help or comment. I want to use "for loop" to calculate series of initial values for an optimization problem. But some initial values have my function quit due to problems like calculating the inverse of singular matrices. I don't want to make my program check determinants and skip it if it is

Hello I'm trying to solve two sets of equations (each set has four equations and all of them share common parameters) with nlminb procedure. I minimize one set and use their parameters as initial values of other set, repeating this until their parameters become very close to each other. I have several parameters (say,param1, param2) and their constraints are given as inequality and depend