similar to: newton.method

Displaying 20 results from an estimated 1000 matches similar to: "newton.method"

2011 Aug 10
3
Need help on Newton-Raphson optimization
Hi, Is there available package on the optimization function using Newton-Raphson method (iterative quadratic approximation)? I have been using the 'optim' function in R and found it really unstable (it depends heavily on the initial values and functional forms). If I have to code it by myself, can I get some advice on how to start (any good reference or sample code)? I really
2011 Aug 14
1
Solving a equation
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.
2010 Mar 11
4
help about solving two equations
I have two matrix s1 and s2, each of them is 1000*1. and I have two equations: digamma(p)-digamma(p+q)=s1, digamma(q)-digamma(p+q)=s2, and I want to sovle these two equations to get the value of x and y, which are also two 1000*1 matrices. I write a program like this: f <- function(x) { p<- x[1]; q <- x[2]; ((digamma(p)-digamma(p+q)-s1[2,]) )^2 +((digamma(q)-digamma(p+q)-s2[2,]) )^2
2017 Jun 12
2
Possible with enableJIT function
In this email to the R-help list: https://stat.ethz.ch/pipermail/r-help/2017-June/447474.html and in this question on Stackoverflow: https://stackoverflow.com/questions/44486643/nleqslv-memory-use-in-r Andrew Leach has raised a question about the memory usage of my package nleqslv. In a model with a loop within a function he has experienced continuously increasing memory usage by package nleqslv
2005 Jun 01
2
Different versions, different results ?
Dear all, I wrote the following batch script on a iMac, and ran it on a linux mosix cluster. tu <- read.table("cage.mm5.tags.rna_lib.CAA-CAJ.tu-reshape.table") tu_reshaped <- t(reshape(tu[1:50,], direction="wide", timevar="tu", idvar=c("rna","lib"))) write.table(tu_reshaped, "cage.mm5.tags.rna_lib.CAA-CAJ.tu-reshaped.table")
2001 Jul 04
2
IPv6 and sshd
Hello, I am having a some problems getting SSHD to run on the Ipv6 interface. Interface/Ipv6 Address: ipv6.open-systems.org [kevin at satan kevin/xp-0.0.15] 536 $ping6 ipv6.open-systems.org PING6(56=40+8+8 bytes) 3ffe:1200:3028:ff01::cab --> 3ffe:1200:3028:ff01::caa 16 bytes from 3ffe:1200:3028:ff01::caa, icmp_seq=0 hlim=64 time=73.96 ms sshd_config: ListenAddress
2012 Mar 20
2
SE from nleqslv
Dear R-users, I use the "nleqslv" function to get parameter estimates by solving a system of non-linear equations. But I also need standard error for each of estimates. I checked the nleqslv manual but it didn't mention about SE. Is there any way to get the SE for each estimate? Thank you very much. [[alternative HTML version deleted]]
2012 Feb 22
1
Good and modern Kernel Regression package in R with auto-bandwidth?
Hi all, I am looking for a good and modern Kernel Regression package in R, which has the following features: 1) It has cross-validation 2) It can automatically choose the "optimal" bandwidth 3) It doesn't have random effect - i.e. if I run the function at different times on the same data-set, the results should be exactly the same... I am trying "np", but I am seeing:
2009 Apr 20
1
Two or more dimensional root (Zero) finding
Good morning to all, I should find the zero of a specific function with respect to a vector of arguments. Does it exist something similar in R? Thank you very much, Enrico Foscolo
2011 Apr 23
2
Loop and Solver with Black/Scholes-Formula
Hello, for my diploma thesis I need to program a solver for Merton?s respectively Black?s and Scholes? Option pricing formula, which should be achieved for several dates. What I want to do is to estimate the value of a firm?s assets "vA" (x[2] denotes vA) and the option-implied volatility of firm?s assets "sigA" (x[1] denotes sigA) by solving it simultaneous using the Black
2014 Aug 25
3
dubious behaviour of match.arg() with nested functions.
Dear all, I initially ran into this problem while rebuilding a package dependent on nleqslv. I got the following error: Error in match.arg(global) : 'arg' must be of length 1 This didn't occur in previous versions of nleqslv, but did in the current one (2.4). I think I pinned the problem down to the following example: Take two functions: test <-
2013 Mar 04
2
[LLVMdev] llvm cannot iterate a [3 x i8]
Hello everyone, I am trying to "parse" a part of LLVM IR. More exactly, from @.str = private unnamed_addr constant [3 x i8] c"DS\00", section "llvm.metadata" I want to get "DS". It is the single place in the whole bytecode from where I can get it. I have : ... Value *VV = cast<Value>(LD100->getOperand(1)->getOperand(0));
2017 Dec 08
2
CAA records using PowerDNS from EPEL
PowerDNS supports CAA records beginning with version 4.0, but the pdns package in EPEL for most recent centos versions is stuck at around version 3.4 (3.4.11 is what I have). Do I have no other choice but to manually compile and maintain my own pdns installation? I prefer to avoid this but I need up-to-date features. Perhaps there is a PowerDNS specific work-around? Maybe the EPEL
2017 Jun 11
1
Memory leak in nleqslv()
Hello all, I am relatively new to R, but enjoying it very much. I am hoping that someone on this list can help me with an issue I am having. I am having issues with iterations over nleqslv, in that the solver does not appear to clean up memory used in previous iterations. I believe I've isolated the/my issue in a small sample of code: library(nleqslv) cons_ext_test <- function(x){
2012 Sep 09
1
Solving a system of two equations
Hi, I am trying to find a simple way to numerically solve a system of two equations equal to zero with two unknowns (x_loc and y_loc). Here is a mock data set and below it, the equations I need to solve. theta<-c(180,135,90)/(2*pi) x<-c(0,0,15) y<-c(20,0,0) 0 = -sum((y_loc-y)*(sin(theta)*(x_loc-x)-cos(theta)*(y_loc-y))/(((x_loc-x)^2+(y_loc-y)^2)^0.5)^3) 0 =
2012 Jul 23
2
Solving equations in R
Hi there, I would like to solve the following equation in R to estimate 'a'. I have the amp, d, x and y. amp*y^2 = 2*a*(1-a)*(-a*d+(1-a)*x)^2 test data: amp = 0.2370 y= 0.0233 d= 0.002 x= 0.091 Can anyone suggest how I can set this up? Thanks, Diviya [[alternative HTML version deleted]]
2017 Feb 09
3
Ancient C /Fortran code linpack error
> > On 9 Feb 2017, at 16:00, G?ran Brostr?m <goran.brostrom at umu.se> wrote: > > > > In my package 'glmmML' I'm using old C code and linpack in the optimizing procedure. Specifically, one part of the code looks like this: > > > > F77_CALL(dpoco)(*hessian, &bdim, &bdim, &rcond, work, info); > > if (*info == 0){ > >
2011 Dec 19
1
None-linear equality constrained optimisation problems
Dear R users, I have a problem. I would like to solve the following: I have pL = 1/(1+e^(-b0+b1)) pM = 1/(1+e^(-b0)) pH = 1/(1+e^(-b0-b1)) My target function is TF= mean(pL,pM,pH) which must equal 0.5% My non-linear constraint is nl.Const = 1-(pM/pH), which must equal 20%, and would like the values of both b0 and b1 where these conditions are met. I have searched widely for an answer,
2017 Feb 09
3
Ancient C /Fortran code linpack error
In my package 'glmmML' I'm using old C code and linpack in the optimizing procedure. Specifically, one part of the code looks like this: F77_CALL(dpoco)(*hessian, &bdim, &bdim, &rcond, work, info); if (*info == 0){ F77_CALL(dpodi)(*hessian, &bdim, &bdim, det, &job); ........ This usually works OK, but with an ill-conditioned data
2010 Sep 02
3
Simultaneous equations
Dear all, I am relatively new to R and have had some difficulty in understanding the user manual for a package that I have downloaded to evaluate non-linear simultaneous equations. The package is called systemfit. Does anyone have any experience of this package? What I am trying to do is solve a non linear simultaneous equations... Could anyone give me an example (please) of the code that