similar to: Numerical integration of a two dimensional function over a disk

Displaying 20 results from an estimated 4000 matches similar to: "Numerical integration of a two dimensional function over a disk"

2012 Mar 25
1
cubature
Hi, I am using adaptIntegrate from Cubature to do numerical integration on a double integral with a 1 x 2 vector x. Say the function is something simple to start like f(x)=x1*x2 and I wish to integrate x1 over (0,365-x2) and x2 over (0,365) f <- function(x) {(x[2])*(x[1])} # "x" is vector int1<-adaptIntegrate(f, lowerLimit = c(0, 0), upperLimit = c(365-x[2], 365)) I recieve
2018 Dec 07
2
Matriz de Datos
Hola Comunidad, Queria consultarles algo, Tengo una data con la siguiente estructura Descripcion Grupo Monto a 1 1.826 a 2 3.497 a 1 4.749 b 1 3.999 b 1 1.638 b 3 4.445 c 2 4.935 c 1 2.299 c 3 1.111 Y quiero crear una matriz que a la fila tenga la descripcion y en la columna el
2011 Nov 10
2
performance of adaptIntegrate vs. integrate
Dear list, [cross-posting from Stack Overflow where this question has remained unanswered for two weeks] I'd like to perform a numerical integration in one dimension, I = int_a^b f(x) dx where the integrand f: x in IR -> f(x) in IR^p is vector-valued. integrate() only allows scalar integrands, thus I would need to call it many (p=200 typically) times, which sounds suboptimal. The
2013 Mar 21
1
"adaptIntegrate" function
Hi all, it seems that there is problem with function "adaptIntegrate", when the integration limits is infinity. Please see the code below. The second integration does not seem to work. Can anyone familiar with this give some help? Thank you with much. Hanna library(mnormt) library(cubature) ff <- function(x, rho){ mu <- rep(0,3) Sigma
2006 Jan 13
3
Can I ask for the C code inside an R function using .C?
Hello, all, It is a general question, but I couldn't find the answer elsewhere. I am using an R function using .C but don't understand one of its behaviors without the C code. I am wondering the so-called 'open source'. It doesn't include the C code together with the R function, does it? So what I want to ask is whether it is justified, possible or polite to ask for the C
2010 Sep 21
3
bivariate vector numerical integration with infinite range
Dear list, I'm seeking some advice regarding a particular numerical integration I wish to perform. The integrand f takes two real arguments x and y and returns a vector of constant length N. The range of integration is [0, infty) for x and [a,b] (finite) for y. Since the integrand has values in R^N I did not find a built-in function to perform numerical quadrature, so I wrote my own after
2008 Aug 15
2
How to substitute special characters within a data frame?
Hello all, I have a data frame in R, imported from an excel file in Swedish. The original file contains several columns that have special characters, such as \¨{a}, \¨{o}, and so on. After import such special characters are represented in the data frame by "\\345", "\\366" etc (don't ask me why). For example, a word "Hårkan" becomes ''H\\345rkan".
2011 May 03
2
adaptIntegrate - how to pass additional parameters to the integrand
Hello, I am trying to use adaptIntegrate function but I need to pass on a few additional parameters to the integrand. However, this function seems not to have the flexibility of passing on such additional parameters. Am I missing something or this is a known limitation. Is there a good alternative to such restrictions, if there at all are? Many thanks for your time. HC -- View this message in
2013 Jan 08
2
Integration in R
Hi R-users. I'm having difficulty with an integration in R via the package "cubature". I'm putting it with a simple example here. I wish to integrate a function like: f(x1,x2)=2/3*(x1+x2) in the interval 0<x1<x2<7. To be sure I tried it by hand and got 114.33, but the following R code is giving me 102.6667.
2012 Oct 02
3
Integration in R
Dear R-users, I am facing problem with integrating in R a likelihood function which is a function of four parameters. It's giving me the result at the end but taking more than half an hour to run. I'm wondering is there any other efficient way deal with. The following is my code. I am ready to provide any other description of my function if you need to move forward.
2013 Feb 16
3
two dimensional integration
Dear R-users, I'm wondering how to calculate this double integral in R: int_a^b int_c^y g(x, y) dx dy where g(x,y) = exp(- alpha (y - x)) * b Thanks for answering! Cheers, Alui [[alternative HTML version deleted]]
2013 Apr 22
2
numerical integration of a bivariate function
hello I work on the probabilities of bivariate normal distribution. I need integrate  the following function. f (x, y) = exp [- (x ^ 2 + y ^ 2 + x * y)] with - ∞ ≤ x ≤ 7.44 and - ∞ ≤ y ≤ 1.44   , either software R or  matlab Version R 2009a Thank you for helping me Regards Mezouara hicham PhD in Metrology Hicham_dess @ yahoo.fr [[alternative HTML version deleted]]
2006 Aug 09
1
minimization a quadratic form with some coef fixed and some constrained
Hello, all, I had problems with an extension to a classic optimization problem. The target is to minimize a quadratic form a'Ma with respect to vector b, where vector a=(b',-1)', i.e., a is the expand of b, and M is a symmetric matrix (positive definite if needed). One more constrain on b is b'b=1. I want to solve b given M. I tried but it seems impossible to find an analytic
2008 Jun 01
2
how to analyze time series structures?
h?, I am preparing undergraduate thesis If you help me this would make me feel good. First I need to analyze effect of Dow Jones Industrial average(DJIA)'s return on Istanbul Stock Exchange(ISE). I want to use Markov-Switching Bayesian Vector Autoregression Models (MSBVAR) that is used to examine the effect of a large economy?s stock exchange movement on a small economy?s stock exchange
2012 May 23
0
Error from using adaptIntegrate within a function that is then integrated
I want to measure the error in the estimation of a 2 dimensional density function that is calculated using an integral but run into problems trying to integrate with adaptIntegrate because the integrand also calls the function adaptIntegrate. In particular I want \int \hat{f}(x,y) - f(x,y) dx dy where \hat{f}(x,y) = \int K(a,b, x, y) da db and in this simulation study I know what the true value
2011 Dec 02
1
R2Cuba package, failed with message ‘Dimension out of range’
Hi All, I get the message failed with message ‘Dimension out of range’ when using cuhre in package R2Cuba. Does anyone know what this mean? Or would I need to email the package author? The funny thing is it does give a result and comparing it to "adaptIntegrate" in package cubature, the two numbers are very close. Thanks, Sachin [[alternative HTML version deleted]]
2013 Mar 05
2
Error message
Dear all, I got an error message when running the following code. Can anyone give any suggestions on fixing this type of error? Thank you very much in advance. Hanna > integrand <- function(x, rho, a, b, z){ + x1 <- x[1] + x2 <- x[2] + Sigma <- matrix(c(1, rho, rho, 1), 2,2) + mu <- rep(0,2) + f <-
2011 Jan 27
0
adaptIntegral takes too much time
Hello Dear List members, as you can see (and guess) from the code below adaptIntegrate(f,lowerLimit=c(-1,-1),upperLimit=c(.9999,.9999)) $integral [1] 9.997e-09 $error [1] 1.665168e-16 $functionEvaluations [1] 17 $returnCode [1] 0 > adaptIntegrate(f,lowerLimit=c(-1,-1),upperLimit=c(1,1)) the last command runs for 45 mins now. -this one takes only less than sec:
2012 May 21
0
Erratic error with adaptIntegrate in cubature package
Hi everyone, I have been using adaptIntegrate from the cubature package for a multidimensional integral that has infinite variance (and so not appropriate for Monte Carlo techniques). Most of the time it works but sometimes (though not always) when I slightly increase the accuracy I want, or increase the bounds of integration I get the following error: REAL() can only be applied to a
2004 Sep 27
1
Numerical two-dimensional integration
Dear all, I need to compute (numerically) the two-dimensional integral: int(int f(x,y)dy)dx. What is the more efficient(fast) way to do it? Is adapt function appropriate for this problem? I will much appreciate your help and attention. Vicky. [[alternative HTML version deleted]]