similar to: How to get solution of following polynomial?

Dear R people: Is there a way to perform simple polynomial multiplication; that is, something like (x - 3) * (x + 3) = x^2 - 9, please? I looked in poly and polyroot and expression. There used to be a package that had this, maybe? thanks, Erin -- Erin Hodgess Associate Professor Department of Computer and Mathematical Sciences University of Houston - Downtown mailto: erinm.hodgess at

Awaiting some suggestion. Was my question not very understandable? Please let me know how can I offer more elaborate clarification. Additionally, I would like to solve the determinant of "p1" for the values of "z" (I am working with some multivariate time series modelling). When I use det() function, it am getting error that, that function is not for objects with class

Hi, I'm a student studing for Math. & Infor. Ing. in Tirana,Albania and a have a final project in R to finish in a week, so I badly need your help... The topic of the project is "Hermite Interpolation" and a I have allready done a script that finds the approximation in a certan point x, H(x) ~f(x) but i want to find the value of his derivative H'(x)~f'(x) as well and to

Are there implementations of, e.g. Neville's algorithm, for interpolating polynomials through some data points? Nevilles' is an improvement on Lagrange interpolation. And how about interpolating rational functions? I could not find anything at rseek.org or at crantastic.org. thanks -- View this message in context:

Hello, I have 3 columns : a, b and a*b I would like to find the pair (a,b) so that a*b is the minimum but not from the points I measured but from the fit of the curve (I have more points that the ones given below but I fit only on this part because I know that the minimum a*b is in this interval). I thought doing it this way : - to fit a*b=f(a) abfit<-lm(ab ~ poly(a,8,raw=T)) - to use the

Hi Ruben, > I see I missed some curly braces. I also modified spacing a tiny bit. Doesn't seem so. E.g. you have: + if ( !VirtualQuery(addr, &b, sizeof(b)) ) + exit(1); + if( !VirtualProtect(b.BaseAddress, b.RegionSize, PAGE_EXECUTE_READWRITE, &b.Protect) ) Add space after "if". Do not put spaces after "(" and before ")". Same for other

2010/10/9 António Saragga Seabra <antseabra at gmail.com>: > I'm on Windows using MinGW... > > 2010/10/9 OvermindDL1 <overminddl1 at gmail.com> >> >> 2010/10/5 António Saragga Seabra <antseabra at gmail.com>: >> > Hi >> > >> > Thank you for your help! Followed your suggestion closely and changed >> > the >> >

Hi I try parallelising some code using the snow package and the following lines: cl <- makeSOCKcluster(8) pfunc <- function (x) (if(x <= (-th)) 1 else 0) ###correlation coefficient clusterExport(cl,c("pfunc","th")) cor.c.f <- parApply(cl,tms,c(1,2),FUN=pfunc) The parApply results in the error message: > cor.c.f <- parApply(cl,tms,c(1,2),FUN=pfunc) Error

Dear list, Did anybody have something like multiroot(), similar to uniroot() only for several varibles/function? I know the difficulty several varibles bring. But for nice functions, it can be useful. We are thinking of writing one....I thought to ask first. Mai Zhou -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read

Hi, That seems really simple... just changing the function pointer. But how to do it for the 'printd' function in the Kaleidoscope example? An example how to do this would be super-great. Any help will be much appreciated. Thanks! On Sat, Oct 9, 2010 at 3:55 PM, OvermindDL1 <overminddl1 at gmail.com> wrote: > 2010/10/9 António Saragga Seabra <antseabra at gmail.com>:

Hi all, I have a polynomial (a big one) and I would like to find a root of it between [-inf, -3] (it's known there is one root in this interval)... How to find that root? In using "uniroot" I need to supply the bounds.... In using "polyroot" I need to write it in the strict sens polynomial format... but I cannot... i.e. the polynomial is implicit... Thank you!

I compiled and tried rsync 2.5.0 but could not get the server running. loadparm.c:string_set() now calls free() which it did not do in 2.4.6 and this free() tries to free memory that was not allocated with malloc. Here is a gdb run (done after adding return before fork() in become_daemon) which shows where it crashes and what my minimal config file for demonstrating the bug was. The config file

I've just encountered a segfault when using DierckxSpline::percur function. Below is the minimal example which triggers the error: --- library(DierckxSpline) x <- 1:10 y <- rep(0, 10) pspline <- percur(x, y) --- *** caught segfault *** address (nil), cause 'memory not mapped' Traceback: 1: .Fortran("percur", iopt = as.integer(iopt), m = as.integer(m), x =

Hi, Attached is a patch for compiler-rt to allow it to compile with MinGW-w64 on Windows. Results aren't that bad. x86 GCC and Clang do everything right, all tests pass. x86_64 GCC fails a lot of tests. This is 99% sure a codegen issue. 38 - fixunssfti_test (Failed) 74 - fixunsdfti_test (Failed) x86_64 Clang fails these tests: 2 - udivmodti4_test (SEGFAULT) 6 - fixdfti_test (Failed) 8 -

I need to solve a equation like this : a = b/(1+x) + c/(1+x)^2 + d/(1+x)^3 where a,b,c,d are known constant. Is there any R-way to do that? Thanks in advance -- View this message in context: http://www.nabble.com/How-to-solve-following-equation--tp20785063p20785063.html Sent from the R help mailing list archive at Nabble.com.

Hello, I am trying to find the analytical solution to this differential equation dR/dt = k1*(R^k2)*(1-(R/Rmax)); R(0) = Ro k1 and k2 are parameters that need to fitted, while Ro and Rmax are the baseline and max value (which can be fitted or fixed). The response (R) increases initially at an exponential rate governed by the rate constants k1 and k2. Response has a S-shaped curve as a function

I have a function address held in an uint64_t. I would like to cast the function address to a function prototype and create a call to the function in LLVM. How could I do this ? Thanks Xin

Hi! I´m need a function that solves the equation f(x) = 0 (i.e. the root of the function) when f is a nonlinear function. Is there any? I´ve tried nlm and optim on the square of the function but the solution is very unstable. Thanks before hand. / Fredrik Thuring ------------------------------------------------------------------------------ This e-mail and any attachment may be confidential

Hi all, This is probably a blindingly obvious question: Why does it matter in the uniroot function whether the f() values at the end points that you supply are of the same sign? For example: f <- function(x,y) {y-x^2+1} #this gives a warning uniroot(f,interval=c(-5,5),y=0) Error in uniroot(f, interval=c(-5, 5), y = 0) : f() values at end points not of opposite sign #this doesn't give a

Hi, I would like to know whether there exist algorithms to compute the coefficients or, at least, the degree of the minimal polynomial of a square matrix A (over the field of complex numbers)? I don't know whether this would require symbolic computation. If not, has any of the algorithms been implemented in R? Thanks very much, Ravi. P.S. Just for the sake of completeness, a