similar to: Help with workaround for: Function '`[`' is not in thederivatives table

# This works fine: > a <- 1 > b <- 2 > c <- 3 > E <- expression(a * exp(b*X) + c) > X <- c(0.5, 1.0, 2.0) > eval(E) [1] 5.718282 10.389056 57.598150 > D(E, "b") a * (exp(b * X) * X) > eval(D(E, "b")) [1] 1.359141 7.389056 109.196300 # But if (a,b,c) are replaced with (A[1], A[2], A[3]), how can I get a derivative

Dear R-users! I am using R 1.7.0, under Windows XP. Having some hospital discharge data (admission date and discharge date for each patient), I want to get the number of patients in the hospital on a given date. My data look like (simple example): > x <- data.frame(patid=c("pat1", "pat2"), adm.date = c("15.03.2002", "16.03.2002"),

the content of th character vector (of length 1) is as follows: a <- "something2 ....pat1 name1 pat2 something2....pat1 name2 pat2....pat1 name3 pat2 " I would like to extract the character bewteen pat1 and pat2. That's to say, I would like to get a vecter of c("name1", "name2","name3"). What I did is use strsplit() twise. But I wonder if there

hi evryone, the command netstat -patn | grep LISTEN shows the next line tcp 0 0 ::1:6010 :::* LISTEN 5195/1 and the command ps ax|grep 5195 shows 5195 ? Ss 0:00 sshd: root at pts/1 i was thinking if this is normal when i connect to the server through ssh, but in another server centos doesn't appear a similar line in the netstat

Full_Name: Martin O'Gorman Version: OS: Submission from: (NULL) (84.176.63.149) I have been looking at the PPC package and have a question. As the input data is comma separated, shouldn?t the command to read in the raw (no batch) mass spec data indicate that sep=?,? (marked below) ? Otherwise, the data read in is the pair of values (m/z,intensity). It is not obvious why that should be.

Hello, Everyone, I am a student an a new learner of R and I am trying to do my homework in R. I have 10 files need to be read and process seperately. I really want to write the codes into something like "macro" to save the lines instead of repeating 10 times of similar work. The following is part of my codes and I only extracted three lines for each repeating section. data.1 <-

Dear R-helper, Please suggest some methods for my question below. We measured the amount of protein A in patient blood in pre-treatment and post-treatment condition from 32 patients. -------------------------------------------- Pre-treatment Post-treatment Pat1 25 28 Pat2 19 15 Pat3 94

Dear all, I'm setting up a connection via XLITE softphone and asterisk 1.4 but I get the error: *Registration error: 404 Not found* Here my configuration file of asterisk: *[root at dhcppc0 asterisk]# vi sip.conf [gianca] type=friend username=gianca secret=pwd_gianca host=dynamic context=tutorial* *[giusy] type=friend username=giusy secret=pwd_giusy host=dynamic context=tutorial* *[root at

Hi, I'm fairly new to R but I have a large dataset (300000 obs) containing patient material. Some patients came 2-9 times during the three year observation period. The patients are identified by a unique idnr, the sessions can be distinguished using the session date. How can I recode the date of the session to a session id (1-9). This would be necessary to obtain information and do some

How can I delete both rows and columns that do not meet a particular cut off value. Example: > d <- rbind(c(0, 1, 6, 4), + c(2, 5, 7, 5), + c(3, 6, 1, 6), + c(4, 4, 4, 4)) > f <- as.matrix(d) > f [,1] [,2] [,3] [,4] [1,] 0 1 6 4 [2,] 2 5 7 5 [3,] 3 6 1 6 [4,] 4 4 4 4 I would like to delete all

Dear all, Attached is a description of my data, graph and the problem which I need help with. Hope you have time to open the file and help me out. Many thanks, Jenny ---------------------------------

Hi Everyone, I have a question regarding the construction of 3D graphs in 'R', BUT these graphs also need to illustrate movement (with time) of the prostate gland (using radiological techniques). I am not sure how to do this in 'R' although I'm sure there is some way of doing it. Below, I have copied and pasted some of the data with which I'm working on. The data