similar to: ?grep

Dear R-Users, I have a dataframe (''forexdata'') of daily returns from the foreign exchange market for three currencies - British Pound (bp), Canadian Dollar(cd), Deustche Mark (dm) vis-a-vis the US Dollar and the Date Of Trade(yymmdd). For some dates the returns are missing (recorded as zero) as there were no trades in that currency for that date. My task is to substitute the

Hello. I have some problems, when I try to model an optimization problem with some constraints. The original problem cannot be solved analytically, so I have to use routines like "Simulated Annealing" or "Sequential Quadric Programming". But to see how all this works in R, I would like to start with some simple problem to get to know the basics: The Problem: min f(x1,x2)=

Hi, I'm trying to calculate some functions loop, unfortunately my data are decimal numbers that not allow me to get an accurate estimate. I do not want to use neither "round "nor "signif" but I would prefer to have all the information available, (the function loop is generic so you should adapt to all data, not just those in particular). The approximation error is

Hi the following gave me a shock: > atan(2) [1] 1.107149 > atan(2+0i) [1] -0.4636476+0i > or, perhaps more of a gotcha: > atan(1.0001+0i) [1] -0.7853482+0i > atan(0.9999+0i) [1] 0.7853482+0i > evidently atan()'s branch cuts aren't where I thought they were. Where do I look for documentation on this? -- Robin Hankin Uncertainty Analyst National

Hi to all, I am working on design package using survival function. First using PSM and adopting a weibull specification for the baseline hazard , I have got the following results(since weibull has both PH and AFT propreties ,in addition I have used the PPHSm command): Value Std. Error z p (Intercept) 1.768 1.0007 1.77 7.73e-02 SIZE -0.707 0.0895 -7.90 2.80e-15

Hi, I'm wrestling with an analysis of a dataset, which I previously analyzed in SYSTAT, but am now converting to R and was doing a re-analysis. I noticed, however, that the same model yields different results (different sums of squares) from the two programs. I first thought this might be because the two programs use different calculations to get the sums of squares, but the problem

Is it possible to fit a lagged regression, "y[t]=b0+b1*x[t-1]+e", using the function "lag"? If so, how? If not, of what use is the function "lag"? I get the same answer from y~x as y~lag(x), whether using lm or arima. I found it using y~c(NA, x[-length(x)])). Consider the following: > set.seed(1) > x <- rep(c(rep(0, 4), 9), len=9) > y <-

Dear Mao Jianfeng, "r-help-owner" is not the place for help, but: r-help at r-project.org (CC-ed here) In any case, strsplit() does the job, i.e.: > unlist(strsplit("BCPy01-01", "-")) [1] "BCPy01" "01" You can work with the whole variable, like: splitpop <- strsplit(df1$popcode, "-") then access the first part with >

Hi, R-listers, Failed, when I tried to merge df1 and df2 by "codetot" in df1 and "codetoto" in df2. I want to know the reason and how to merge them together. Data frames and codes I have used were listed as followed. Thanks a lot in advance. df1: popcode codetot p3need BCPy01-01 BCPy01-01-1 100.0000 BCPy01-01 BCPy01-01-2 100.0000 BCPy01-01 BCPy01-01-3 100.0000 BCPy01-02

Dear all: I attached the dataset with this email and post codes as below. My questions is related to the 'col=temp.col' for the line and pch in my code, I have 4 IDs, 10 DIDs and each ID include different DIDs, for example, first ID has 3 DIDs, then the color is the first three colors(black, red, green) in the first plot, but in the second plot, why the color change to pink which is

R 2.15.1 OS X and Windows Colleagues, I have a file that looks that this: TABLE NO. 1 PTID TIME AMT FORM PERIOD IPRED CWRES EVID CP PRED RES WRES 2.0010E+03 3.9375E-01 5.0000E+03 2.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 1.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 2.0010E+03 8.9583E-01

Dear all: I have been thinking to import below one data file (.txt)into R by read.table(..,skip=1, header=T). But How can I deal with the repeated rows of TABLE NO.1 and names of data variables in the middle of this data file. The similar block will be repeated 100 times, here only show 4 of them and within each block, data records also can vary, here only paste 4 rows for example. I appreciate

Dear all: I have been thinking to import below one data file (.txt)into R by read.table(..,skip=1, header=T). But How can I deal with the repeated rows of TABLE NO.1 and names of data variables in the middle of this data file. The similar block will be repeated 100 times, here only show 4 of them and within each block, data records also can vary, here only paste 4 rows for example. I appreciate

R 2.15.1 OS X Colleagues, I am reading a 1 GB file into R using read.table. The file consists of 100 tables, each of which is headed by two lines of characters. The first of these lines is: TABLE NO. 1 The second is a list of column headers. For example: TABLE NO. 1 COL1 COL2 COL3 COL4 COL5 COL6 COL7 COL8 COL9 COL10

Dear ReXperts, I have the below text file output. I need to extract the T, QC, QO, QO-QC and WT columns for the data between T = 10 and T=150. Any ideas? Thanks in advance. ======================================================================================== 1 D C ---CAT-- T THETA QC QO QO-QC QC/QO WT FSD 8 1 0 1.0000E+01

System info: Linux slackware R Version 1.5.1 (2002-06-17) ESS 5.1.21 Emacs 21.2.1 ------------------- Colleagues I have some text files in a certain directory and want to process them sequentially. So I want to pass the filename identifier into a function and loop through the processing of each file in turn.I've called the file identifier f in this code segment: image.dvm <- function

Hello, Are there any R functions available for performing a serial correlation test for short time series (e.g, series having between 10-14 observations)? Many thanks! Isabella R. Ghement, Ph.D. Ghement Statistical Consulting Company 301-7031 Blundell Road, Richmond, B.C., Canada, V6Y 1J5 Tel: 604-767-1250 Fax: 604-270-3922 E-mail: isabella at ghement.ca Web: www.ghement.ca -----Original

Greetings, I am working in the sem package on a model with 3 exogenous variables (2 are nominal-categorical), and 4 endogenous, continuous variables. To use sem with the nominal variables, I created dummy variables. Now, in my sem output I have estimates for path coefficients for the relationship between each level of the nominal variables and the endogenous variables they are associated

I have problems getting a histogram with relative frequencies on the y-axis. Here is an example data set: > a <- c(4.626, 4.627, 4.627, 4.628, 4.629, 4.629, 4.630, 4.631, 4.632, 4.632) > d = hist(a,freq=F) > d$density [1] 299.9999 100.0000 200.0000 100.0000 100.0000 200.0000 The obtained densities are given by counts/(total n * bin width), with bin width being

Hi there, as a student sociology, I'm starting to learn about SEM. The course I follow is based on LISREL, but I want to use the SEM-package on R parallel to it. Using LISREL, I found it to be very usable to be able to see the total direct and total indirect effects (standardized and unstandardized) in the output. Can I create these effects using R? I know how to calculate them