Displaying 20 results from an estimated 10000 matches similar to: "numerical integration and 'non-finite function value' error"
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
2012 Oct 20
4
Error in integrate(integrand, 0, Inf) : non-finite function value
Dear R users,
When I run the code below, I get the error "Error in integrate(integrand, 0,
Inf) : non-finite function value". The code works if the function returns
only "sum(integ)". However, I want to add "cmh" to it. When I add "cmh" I
get that error. I can't figure out why this is happening because my
integrate function has nothing to do with
2007 May 24
3
Problem with numerical integration and optimization with BFGS
Hi R users,
I have a couple of questions about some problems that I am facing with
regard to numerical integration and optimization of likelihood
functions. Let me provide a little background information: I am trying
to do maximum likelihood estimation of an econometric model that I have
developed recently. I estimate the parameters of the model using the
monthly US unemployment rate series
2007 Dec 17
3
integration
Dear All,
I need to perform a numerical integration of one dimensional
fucntions. The extrems of integration are both finite and the functions
I'm working on are quite complicated. I have already tried both area()
and integrate(), but they do not perform well: area() is very slow and
integrate() does not converge. Are in R other functions for numerical
integration of one dimentional
2009 Sep 23
1
Numerical integration problem
Hi there
I'm trying to construct a model of mortality risk in 2D space that
requires numerical integration of a hazard function, for which I'm using
the integrate function. I'm occasionally encountering parameter
combinations that cause integrate to terminate with error "Error in
integrate... the integral is probably divergent", which I'm not sure how
to interpret. The
2008 Aug 26
2
Problem with Integrate for NEF-HS distribution
I need to calcuate the cumulative probability for the Natural Exponential Family - Hyperbolic secant distribution with a parameter theta between -pi/2 and pi/2. The integration should be between 0 and 1 as it is a probability.
The function "integrate" works fine when the absolute value of theta is not too large. That is, the NEF-HS distribution is not too skewed. However, once the
2018 Mar 23
1
Integrate erros on certain functions
In the help for ?integrate:
>When integrating over infinite intervals do so explicitly, rather than
just using a large number as the endpoint. This increases the chance of a
correct answer ? any function whose integral over an infinite interval is
finite must be near zero for most of that interval.
I understand that and there are examples such as:
## a slowly-convergent integral
integrand
2009 Dec 18
1
Numerical Integration
Dear @ll. I have to calculate numerical integrals for triangular and trapezoidal figures. I know you can calculate the exactly, but I want to do it this way to learn how to proceed with more complicated shapes. The code I'm using is the following:
integrand<-function(x) {
print(x)
if(x<fx[1]) return(0)
if(x>=fx[1] && x<fx[2]) return((x-fx[1])/(fx[2]-fx[1]))
2008 Mar 07
3
Numerical Integration in 1D
Dear UseRs,
I'm curious about the derivative of n!.
We know that Gamma(n+1)=n! So when on takes the derivative of
Gamma(n+1) we get Int(ln(x)*exp(-x)*x^n,x=0..Inf).
I've tried code like
> integrand<-function(x) {log(x)*exp(x)*x^n}
> integrate(integrand,lower=0,upper=Inf)
It seems that R doesn't like to integrate for any n, and I was
wondering if anyone knew a way around
2006 Aug 26
1
Capture of iterative integration output
Hello,
I am a novice R user and am having difficulty retrieving the values
from 21 iterations of the R function integrate.
The only way I have found is to do a write.table and then a read.table
as shown in the code below. I would rather capture the 21 values inside
the braces ( sapply might work, but I can't set it up without getting an
error in function) so I could compute the
2012 May 23
1
numerical integration
Greetings,
Sorry, the last message was sent by mistake! Here it is again:
I encounter a strange problem computing some numerical integrals on [0,oo).
Define
$$
M_j(x)=exp(-jax)
$$
where $a=0.08$. We want to compute the $L^2([0,\infty))$-inner products
$$
A_{ij}:=(M_i,M_j)=\int_0^\infty M_i(x)M_j(x)dx
$$
Analytically we have
$$
A_{ij}=1/(a(i+j)).
$$
In the code below we compute the matrix
2010 Nov 17
2
Numerical integration
Hi!
I was wondering if there are any other functions for numerical integration,
besides 'integrate' from the stats package, but which wouldn't require the
integrand to be vectorized. Oh, and must be capable of integrating over
(-inf,+inf).
Thanks in advance,
Eduardo Horta
[[alternative HTML version deleted]]
2011 May 30
1
Error in minimizing an integrand using optim
Hi,
Am not sure if my code itself is correct. Here's what am trying to do:
Minimize integration of a function of gaussian distributed variable 'x' over
the interval qnorm(0.999) to Inf by changing value of parameter 'mu'. mu is
the shift in mean of 'x'.
Code:
# x follows gaussian distribution
# fx2 to be minimized by changing values of mu
# integration to be done over
2010 Jan 02
2
ifelse and piecewise function
I am a novice user of "R" and I'm learning with R version 2.8.1, using
WinEdt_1.8.1, under Widows Vista Home Version.
## The test function below, from a vector input, returns vector values:
# and it contains an "ifelse"statement
TEST<- function(x) {
low<- -x^2
up<- x^4
ifelse(x>=0,up,low )
}
u<- seq(-1,1,0.5)
TEST(u)
2013 Feb 15
1
minimizing a numerical integration
Dear all,
I am a new user to R and I am using pracma and nloptr libraries to minimize
a numerical integration subject to a single constraint . The integrand
itself is somehow a complicated function of x and y that is computed
through several steps. i formulated the integrand in a separate function
called f which is a function of x &y. I want to find the optimal value of x
such that the
2007 Aug 23
1
nls() and numerical integration (e.g. integrate()) working together?
Dear List-Members,
since 3 weeks I have been heavily working on reproducing the results of an
economic paper. The method there uses the numerical solution of an integral
within nonlinear least squares. Within the integrand there is also some
parameter to estimate. Is that in the end possible to implement in R
[Originally it was done in GAUSS]? I'm nearly into giving up.
I constucted an
2012 Sep 25
1
how to pass a function to a function inside a function
Hi,
I'm trying to compile two functions into one function. the first funtion is
called 'fs' which is self-made function, another function is from the
built-in 'integration' function that is copy-paste-edited. If built
separatey, these functions work well. However that is not the case if
combines together, where certainly I made mistake somewhere when
constructing the code.
2010 Dec 22
3
How to integrate a function with additional argument being a vector or matrix?
Dear expeRts,
I somehow don't see why the following does not work:
integrand <- function(x, vec, mat, val) 1 # dummy return value
A <- matrix(runif(16), ncol = 4)
u <- c(0.4, 0.1, 0.2, 0.3)
integrand(0.3, u, A, 4)
integrate(integrand, lower = 0, upper = 1, vec = u, mat = A, val = 4)
I would like to integrate a function ("integrand") which gets an "x" value (the
2007 Nov 09
5
Multivariate integration with infinite limits
Dear All,
Can R perform multivariate integration with infinite limits of integration?
Thanks in advance,
Paul
2002 Jun 28
1
integrate function fails! (PR#1718)
Full_Name: José Enrique Chacón
Version: 1.5.0 and 1.3.1
OS: Windows Millenium
Submission from: (NULL) (158.49.28.155)
Dear reader:
I was trying to evaluate the L2 error produced when estimating the density
function N(0,1) from a sample of size 100 using a kernel density estimate. It
produced a strange value. You can reproduce the process by typing
samp<-rnorm(100)