similar to: Solving A System of Equations

Hi there, I have following equations to be solved for a and b: a/(a+b) = x1 ab/((a+b)^2 (a+b+1)) = x2 Is there any direct function available to solve them without disentangling them manually? Thanks for your help.

Friends, I'm trying to pass an equation as an argument to a function. The idea is as follows. Let us say i write an independent function Ideal Situation: ifunc <- function(x) { return((x*x)-2) } mainfunc <- function(a,b) { evala <- ifunc(a) evalb <- ifunc(b) if (evala>evalb){return(evala)} else return(evalb) } Now I want to try and write this entire program in a single

--=-hiYzUeWcRJ/+kx41aPIZ Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit Hi, on March 10 I filed a wishlist bug report asking for the inclusion of some changes to factanal() and the associated print method. The changes were originally proposed by John Fox in 2005; they make print.factanal() display factor correlations if factanal() is called with rotation =

Surprisingly, I played around with some test code and below actually creates equations that look correct. tempmat<-matrix(10,nrow=6,ncol=6) restrictmat<-diag(6) colnames(tempmat)<-c("AUD.l1","CHF.l1","CAD.l1","GBP.l1","EUR.l1","JPY.l 1")

I'm currently working on writing up some documentation for some of my code, but am having the darndest time coding in equations. For example, the equation in the following: \details{ Calculated the R Squared for observed endogenous variables in a structural equation model, as well as several other useful summary statistics about the error in thoe variables. R Squared values are

I'm examining the use of the 'lm' function to solve quadratic functions. With S+ 2000, the 'lm' function can be used to solve eqns such as x1 + x2 + x1^2 + x2^2 + x1*x2. But, when trying this same eqn with R, the software does not produce any coefficients for x1^2 or x2^2. Is this a common problem? I'm using ver. 1.3.1 under Win. 2000. Thanks, Peter

Hi, I am doing a small experiment to test if I can use MathJax ( official site: http://www.mathjax.org ) in R's html help pages (i.e. options(help_type='html')) and it seems working with some minor modifications. The screenshot (rendered by Firefox 4.0 beta and with STIX fonts) of the help page in html format with MathJax enabled is at the following url:

I've been working on a new package and I have a few questions regarding the behaviour of the nlm function. I've been (for better or worse) using the nlm function to fit a linear model without suppling the hessian or gradient attributes in the objective function. I'm curious as to why the nlm requires 31 iterations (for the linear model), and then it doesn't work when I try to add

I should'nt have sent the last mail so fast. Same problem with \eqn{u_j = a_j + b x + c x^2, \quad j=1, \ldots, r-1} {u[j] = a[j] + b*x + c*x^2 j = 1,\dots,r-1} I thought the problem in the first case could have to do with the use use of \mbox{} (with the braces) within the arguments of \eqn, but here there are none braces in the arguments of \eqn{}{}. Another case giving the

Full_Name: Ross Boylan Version: 2.2.0 OS: Linux Submission from: (NULL) (65.175.48.58) \eqn{{\bf\beta}_j}{b(j)} in my .Rd file produces this error -------------------------------------------- ! Missing $ inserted. <inserted text> $ l.7 \eqn{{\bf\beta}_j}{\bf\beta}_ jnormal-bracket5bracket-normal{b(j)} -- ! Missing $ inserted. <inserted

Full_Name: Robin Hankin Version: 2.4.0 RC OS: MacOSX 10.4.7 Submission from: (NULL) (139.166.242.29) The first cut line described in Trig.Rd for asin() is incorrect in the ascii version of the manpage. The Rd file reads: For \code{asin()} and \code{acos()}, there are two cuts, both along the real axis: \eqn{\left(-\infty, -1\right]}{\(-Inf, 1\]} and Note the inconsistency between the

'Writing R Extensions' tells you that $ needs to be escaped in Rd files outside \code and similar. So I was surprised to find that ca 80 CRAN packages have constructions like (from ISwR) \item{\code{folate}}{ a numeric vector, folate concentration ($\mu$g/l). } This does not render sensibly in non-latex conversions, and it is what we have \eqn{} for. That $ needs to be

I want to create a clean .rpm package for R built with MKL and ICC. I follow Fedora instrcutions[0] to create the package. As a base, I use the R-3.2.2.src.rpm. I am left with this error: ------------------------------------------ installing R info pages ... updating '/usr/share/info/dir' ... make[1]: Leaving directory '/home/poisonivy/rpmbuild/BUILD/R-3.2.2/doc/manual' + mv

Dear list, I've tried several times to wrap my head around the Design library, without much success. It does some really nice things, but I'm often uncomfortable because I don't understand exactly what it's doing. Anyway, one thing I really like is the latex.ols() function, which converts an R linear model formula to a LaTeX equation. So, I started writing a latex.lm() function

I've got a package I would like to send out for testing and have noticed a "problem" with the \tabular portion of the help "compiler" the code for inserting vertical lines, in the tabular environment, causes the build to choke, but not the check command. C:\>rcmd build --binary -docs=all nlsystemfit \tabular{|l|c|c|c|}{ \hline Method \tab Instruments \tab

Can some help me spot what I'm doing wrong here. I have two equations, one a michalis-menton eqn and one a straight line. I need to work out where they cross. I created the function: solveEqn<-function(x,vals){ Vmax<-vals[1] Ks<-vals[2] m<-vals[3] c<-vals[4] diff<-0 mmVal<-exp(Vmax+x/(Ks+x)) slVal<-x*m+c diff<-mmVal-slVal return(diff) } >

Hello, I have being trying to estimate the parameters of the?generalized?exponential distribution. The random number generation for the GE distribution is?x<-(-log(1-U^(1/p1))/b), where U stands for uniform dist. The data i have generated to estimate the parameters is right censored and the code is given below; The problem is that, the newton-Raphson approach isnt working and i do not know what

Hola! I have the following in a .Rd file: \eqn{\mbox{coef} = c(\mbox{coef}[1],\ldots, \mbox{coef}[n]) } {coef = c(coef[1], coef[2], \dots, coef[n])} However, both arguments come out in the latex file! Whats happening? Kjetil Halvorsen

Hello! I'm a college undergrad desperately trying to finish up my thesis. I have a dataset on the distribution of a grassland bird from the Breeding Bird Survey. I have a very straightforward and simple version of the logistic growth model to describe changes in this bird's abundance over time. The variables are the natural birth rate, mortality, and carrying capacity. The equation itself

I have constructed the function mml2 (below) based on the likelihood function described in the minimal latex I have pasted below for anyone who wants to look at it. This function finds parameter estimates for a basic Rasch (IRT) model. Using the function without the gradient, using either nlminb or optim returns the correct parameter estimates and, in the case of optim, the correct standard