similar to: can R solve these paired equations

I used the command below, but R gives me the error message--syntax error. can anyone see the mistakes I made? optimize(function(x,y) + ((327.727-(1-0.114^10)*y*(1-x)/x/(1-x^y))+(9517.336-327.727 *(1+(1-x)*(1+y)/x-327.727)))^2 + interval=c(0,1)) At the same time, I use nlm() but R gives me the code $code [1] 3 function(vals) { x <- vals[1] y <- vals[2]

Dear all, I just know how to solve an eaquation by using optim() or nlm(). But, now, I have three nonlinear equations, how could we use optim() or nlm() to solve  a system of nonlinear equations in R?  Thank you so much. Sincerely, Joe ___________________________________________________ 您的生活即時通 － 溝通、娛樂、生活、工作一次搞定！ [[alternative HTML version deleted]]

Hi How do I specify an S4 class with a slot that is potentially numeric, but NA by default? I want the slot to be NA until I calculate its value (an expensive operation, not needed for all applications). When its value is known, I will create a new object with the correct value inserted in the slot. I want "NA" to signify "not known". My attempt fails because

Hey, I was wondering if there existed a R function similar to 'fsolve' or 'fzero' Matlab functions? Thanks! Francois Aucoin [[alternative HTML version deleted]]

Dear All, I have two simple data samples (no groups or factors, etc.) and would just like to compute the two-sample Wilcoxon Rank Sum test using the wilcox_test function contained in the coin package, which is reportedly better than the regular wilcox.test function because it performs some adjustment for ties. Would anyone know how to craft a script to perform this task? Much appreciated. Janh

Dear: I want to plot barplot and let bar be in the middle of each x axis category. Do you have this experience? Many Thanks! Xin [[alternative HTML version deleted]]

Hi suppose I have two arrays x1,x2 of dimensions a1,b1,c1 and a2,b2,c2 respectively. I want x = x1 "+" x2 with dimensions c(max(a1,a2), max(b1,b2),max (c1,c2)) with x[a,b,c] = x1[a1,b1,c1] + x2[a2,b2,c2] if a <=min(a1,a2) , b<=min (b1,b2), c<=min(c1,c2) and the other bits either x1 or x2 or zero according to whether the coordinates are "in range" for

Hello R users, I am trying to estimate the parameters of a bimodal normal distribution using moments matching, so I have to solve a non-linear system of equations. How can I solve the following simple example? x^2 - y^2 = 6 x ? y = 3 I heard about nlsystemfit, but I don?t know how to run it exactly. I have tried the following code, but it doesn?t really work: f1 <-y~ x[1]^2-x[2]^2-6 f2

Dear All: I am trying to read the data from the different sheet but in the same Excel file. Does R provide this kind of command to do it? Anyone has experience on this? Thanks! Xin [[alternative HTML version deleted]]

What is the "classic" R function for solving a (possibly over determined) system of non-linear equations? Thank you! Moshe Olshansky e-mail: moshe.olshansky@brevanhoward.com The information transmitted is intended only for the person(s) or entity to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or

Hi all, I'm trying to estimate model parameters in R for a pretty simple system of equations, but I'm having trouble. Here is the system of equations (all derivatives): eqAlgae <- (u_Amax * C_A) * (1 - (Q_Amin / Q_A)) eqQuota <- (p_max * R_V) / (K_p + R_V) - ((Q_A-Q_Amin)*u_Amax) eqResource <- -C_A * (p_max * R_V) / (K_p + R_V) eqSystem <- list(C_A = eqAlgae, Q_A = eqQuota,

Dear R users, I am trying to minimise a function using "nlm". I am getting the following error message: "Error: function is too long to keep source" The function is really very long (about 100 A4 pages). Is there anything I could do to solve this problem? At the moment I am using "nlmin" in S-Plus with no problems but I'd prefer to use R. Thank you very

hits=1.0 tests=MANY_EXCLAMATIONS X-USF-Spam-Flag: NO Hi I am writing a package for multivariate polynomials ('multipols') using S3 methods. The package includes a Ops.multipol() function for the arithmetic methods; I would like to define some sort of user-specified Boolean option which, if set, would force results to be simplified as they are produced. Call this option

Hi Suppose I have an S4 class "foo" and a validity checking function ".checkfoo()": setClass("foo", representation=representation("numeric")) setValidity("foo" , .checkfoo) is fine; in my application, .checkfoo() verifies that a bunch of necessary conditions are met. But .checkfoo() is very time consuming and I want to give users the option

Dear All: I imported a table into R. But I want to read a variable (y) from this table conditional on another variable (x=1) in the table. y<-data[,7] x<-data[,3] I want to know the mean of y if corresponding x=1. I tried if (x==1) y3<-y It does not work. Anyone can give a help? Thanks! Xin [[alternative HTML version deleted]]

Dear I try to add three different lines (solid, short dash, long dash) in to current barplot. I saw there are types of lines ("p","b", ect). However, they are not what I request. Has nayone have this experience? Many Thanks! Xin [[alternative HTML version deleted]]

Hi [this after some considerable thought as to R-help vs R-devel] I want to write a (S3) method for as.function(); toy example follows. Given a matrix "a", I need to evaluate trace(ax) as a function of (matrix) "x". Here's a trace function: tr <- function (a) { i <- seq_len(nrow(a)) return(sum(a[cbind(i, i)])) } How do I accomplish the following:

Hi, I'm having trouble converting code from MATLAB to R; I want to find the equivalence to MATLAB's function 'fsolve'. I've tried 'nlm', on the squared argument, in R but i did not get the same results. Thankful if helped. Best regards, Martin Englund ------------------------------------------------------------------------------ This e-mail and any attachment may

Dear All: I tried to fit negative binomial distribution to data in terms of mean and mean is also a quadratic function of another variable. The likelihood function is: function (parameters, y1,x11) { p<-parameters[1] alpha1<-parameters[1] beta1<-parameters[2] delta1<-parameters[3] mu<-alpha1+beta1*(x11)+delta1*(x11^2) ifelse(y1>=0|x11>=0, L<-

Dear All: I used optim() to minimise the loglikelihood function for fitting data to negative binomial distribution. But there initial value of log-likelihood and iteration 10 value are reasonable. for example: initial value 1451657.994524 iter 10 value 47297.534905 iter 20 value -623478636.8236478 Then the iter 20 vlaue suddelnly changes to a negative value and in the end the error mesage is