similar to: Precision in R

Hello I am trying to evaluate an Incomplete gamma function in R. Library Zipfr gives the Igamma function. From Mathematica, I have: "Gamma[a, z] is the incomplete gamma function." In[16]: Gamma[9,11.1] Out[16]: 9000.5 Trying the same in R, I get > Igamma(9,11.1) [1] 31319.5 OR > Igamma(11.1,9) [1] 1300998 I know I have to understand the theory and the math behind it rather

Hello I want to calculate natural logarithm of sum of combinations as follow: (R code) { com_sum=choose(2000000,482)*choose(1000000,118)+choose(2000000,483)*choose(1000000,117)+...+choose(2000000,i)*choose(1000000,600-i)+...+choose(2000000,600)*choose(1000000,0) #calculate the sum result=log(com_sum) #calculate the log of the sum } But

Hello I have a time-comsuming program which need to simplify, I have tested the annotated program as follow: > #define function which will be call > calsta <- function(c, n=100000) + { + i <- seq(from=0, length=c) + logx <- lchoose(NT-n, CT-i) + lchoose(n, i) + logmax <- max(logx) + logmax + log(sum(exp(logx - logmax))) + } > CT=6000 #assignment to CT >

Dear all, Is there a reason, why there is no +-operator for aes (i.e. uneval) objects (as there is for themes and gg objects)? I had a couple of cases where such an operator would be useful, for instance to combine the result of aes and aes_string in functions. Any flaws with the following proposition: `+.uneval` <- function(e1, e2) { dup <- names(e1) %in% names(e2) if (any(dup)) {

Hello, I'd like to take all possible sub-summands of a vector in the quickest and most efficient way possible. By "sub-summands" I mean for each sub-vector, take its sum. Which is to say: if I had the vector x<-1:4 I'd want the "sum" of x[1], x[2], etc. And then the sum of x[1:2], x[2:3], etc. And then...so on. The result would be: 1 2 3 4 2 5 7 6 9 10 I can

Hi, I would like to apply the L-BFGS optimization algorithm to compute the MLE of a multilevel multinomial Logistic Regression. The likelihood formula for this model has as one of the summands the formula for computing the likelihood of an ordinary (single-level) multinomial logit regression. So I would basically need the R implementation for this formula. The L-BFGS algorithm also requires

I am a newbie to C (although I did some programming in Perl and Pascal) so forgive me for the language that follows. I am writing because I have a question concerning the *implementation of *(the internal function)* cwilcox* in https://svn.r-project.org/R/!svn/bc/81274/branches/R-DL/src/nmath/wilcox.c. This function is used to determine the test statistics of the Wilcoxon-Mann-Whitney U-test.

Dear friends. In Carlin and Louis "Bayes and emperical Bayes methods.." 1996 the classical example of 12 independent tosses of a fair coin producing 9 heads and 3 tails is given. If the situation is seen as a fixed sample of 12, a binomial lieklihood is used, and Carlin et al reports a probability of 0.075. Using sum(dbinom(9:12,12,.5)) I obtain 0.073 Likewise, if the experiment is

Folks, This is so simple is driving me crazy. It's not really an R question is more an Statistics question. I applied a chemical in 3 different events during a growing season. I took 3 samples in each event to estimate mean applied chemical. Thus, I can easily estimate means and st.err by event. I can then estimate the total chemical applied for the whole season by adding the 3 means

Hello T I want to order some calculation "result", there will be lots of "result" that need to calculate and order PS: the "result" is just a intermediate varible and ordering them is the very aim # problem: # For fixed NT and CT, and some pair (c,n). order the pair by corresponding result # c and n are both random variable CT<-6000 #assignment to CT

Dear list, I am trying to follow an example that estimates a 2x2 markov transition matrix across several periods from aggregate data using restricted least squares. I seem to be making headway using solve.QP(quadprog) as the unrestricted solution matches the example I am following, and I can specify simple equality and inequality constraints. However, I cannot correctly specify a constraint

Hi, I'm quite new to the R-project. I was suggested to look into it because I am trying to solve the "Subset sum" problem", which basically is: Given a set of integers and an integer s, does any non-empty subset sum to s? (See http://en.wikipedia.org/wiki/Subset_sum_problem) I have been searching the web for quite some time now (which is how I eventually discovered that my