Displaying 20 results from an estimated 1000 matches similar to: "Manipulate solution of simplex"
2002 Nov 22
1
simplex problem (PR#2317)
Full_Name: George F. LeCompte
Version: 1.6.1
OS: Windows 98
Submission from: (NULL) (208.8.162.161)
This may be a newbie problem. I am attempting tor unt the simplex routine from
the boot package. The example code doesn't find simplex. What's wrong here?
> help(simplex,package=boot)
> # from the resulting article
>
> # This example is taken from Exercise 7.5 of
2007 Jul 10
2
integration over a simplex
Hello
The excellent adapt package integrates over multi-dimensional
hypercubes.
I want to integrate over a multidimensional simplex. Has anyone
implemented such a thing in R?
I can transform an n-simplex to a hyperrectangle
but the Jacobian is a rapidly-varying (and very lopsided)
function and this is making adapt() slow.
[
A \dfn{simplex} is an n-dimensional analogue of a triangle or
2009 Dec 08
1
Simplex Density Plots
Hello,
I have just started using R, and have found it quite easy to make
plots of probability densities for normal and beta distributions, etc.
Now, I'm looking at trying to make a simplex plot of a Dirichlet
density, but have gotten stuck and was hoping that someone could help.
Ideally, the plot would look something like the 3d plots on Wikipedia here:
2009 Oct 10
2
Nelder-Mead with output of simplex vertices
Greetings!
I want to follow the evolution of a Nelder-Mead function
minimisation (a function of 2 variables). Hence each simplex
will have 3 vertices.
Therefore I would like to have a function which can output
the coordinates of the 3 vertices after each new simplex
is generated. However, there seems to be no way (which I can
detect) of extracting this information from optim() (the
2008 Dec 11
2
Simplex function in R
I have a set of linear equations and would like to find any feasible solution. A simplex solution works in Case 1 below, but not in Case 2. I would be grateful for any help.
Case 1: Find any feasible solution for the set of linear equations:
a + b + c = 5
a + b + 0c = 4
0a + b + c = 4
Solution - a feasible (and unique) solution is a=1, b=3, c=1.
The following R code
2003 Oct 11
1
Simplex "Out of Bounds" Error
I am running the following code (testing the use of the simplex function to
determine if a point is in the convex hull of another set of points or not):
>a <- c(0, 0)
>A3 <-matrix(c(1,2,3,4,1,1), ncol = 2, byrow = T)
>b3 <-c(1.5, 3.5, 1)
>simplex(a = a, A3 = A3, b3 = b3)
and the following error message appears:
Error in simplex1(out1$a[1:(n + m1 + m2)], out1$A[, 1:(n + m1
2005 Mar 11
1
Simplex(boot) returning invalid answer
In trying to use simplex() from the boot package, I have run into a
situation that doesn't seem like it should be possible. It is claiming
that it has solved the LP, but returns a vector of all zeros, which
does not satisfy the constraints I passed in. A small example:
> ubMatrix <- matrix(c(1,1,-1,0,-1,-1), 3, 2)
> ubVector <- c(2,1,-1)
> objective <- c(0,1)
>
2007 Nov 30
1
simplex projection and S-Map
I am interested in using the nonlinear forecasting techniques developed
by Sugihara et al. In particular the simplex projection and the S-Map
(see this website for details and reprints: http://iod.ucsd.edu/simplex/ ).
I've looked through CRAN but could not find any package with functions
that allow such analysis.
Any pointers?
Thanks,
Manu
2006 Oct 08
2
Error Correcting Codes, Simplex
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2009 Jun 23
1
Forecast GARCH model
Hi,
I've fitted a GARCH(1,1) for the residuals of my time serie (X).
X is an ARMA(1,1) process.
Now I want to do a n-step forecast for X, knowing these processes. How can I
do this?
I know that there's a command:
predict() for ARIMA processes and so on, but what about GARCH?
I've got:
arma=arima(x, order=c(1,0,1))
(...)
garch11<-garch(residuals(x),order = c(1, 1))
2003 Apr 02
1
n.iter in simplex()
Dear R users,
Is anyone familiar with the "n.iter" argument of the simplex() function
(in the boot package)? It seems it doesn't have an effect no matter what
value I set it ...
I'm trying to solve a linear programming problem and running into the
problem of
simplex.object$solved = 0
or
"A value of 0 indicates that the maximum number of iterations was reached
without
2010 Oct 23
1
contour on a simplex
Hello,
anyone knows if there is a way in R to draw contour on a simplex based on a
function f(x,y,z) with domain (x+y+z = 1)?
Thank you!
gigi
[[alternative HTML version deleted]]
2002 Sep 25
1
rbind(NULL,NULL) and simplex()
Hello everybody.
I found out the other day something quite astonishing (which I guess
is not astonishing at all to those in the know): in d-dimensional
space, determining whether a given point is inside the convex hull of
a set of n points is elegantly and quickly solvable using linear
programming.
If the columns of matrix "ff" are the coordinates of the set of
points, then in d=2
2009 May 30
2
Simplex voice on TDM410P
Hello,
I am working on a trixbox based system with a TDM410P connected to 3
phone lines from the CO. The asterisk box is on a full duplex 100Mb LAN
with some polycom and Aastra SIP phones. In general everything works.
the problem I am trying to solve is that if both parties to a call speak
at the same time one of the voices gets cut out such that the talker A
cannot hear what talker B is
2002 Jan 25
0
Simplex difficulties
I'm exploring the simplex algorithm with a simple transportation problem
of the form:
minimize:
8a + 6b + 10c + 9d + 5e + 7f
subject to the constraints:
a + b + c = 11
d + e + f = 14
a + d = 10
b + e = 8
c + f = 7
I've implemented this in R (1.4.0 (2001-12-19), SunOS 5.7) as:
require(boot)
costs = c(8,6,10,9,5,7)
constraints = c(
1,1,1,0,0,0,
0,0,0,1,1,1,
1,0,0,1,0,0,
2004 Jan 14
4
re hardware requirement - asterisk
I have just checked the Openbsd box on the if interface.
fxp0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
address: 00:02:55:30:54:28
media: Ethernet autoselect (100baseTX full-duplex)
status: active
inet 192.168.1.1 netmask 0xffffff00 broadcast 192.168.1.255
inet6 fe80::202:55ff:fe30:5428%fxp0 prefixlen 64 scopeid 0x1
xl0:
2013 Apr 02
1
R doesn't recognize utils functions, such as arrayIndex( )
Hi all,
When I called arrayIndex(20:23, dim=c(4,3,3)), it says "Error: could not
find function "arrayIndex"in R". So I called ls("package:utils") to see the
functions inside:
[1] "?"
[2] "adist"
[3] "alarm"
[4] "apropos"
[5] "aregexec"
[6] "argsAnywhere"
[7] "arrangeWindows"
[8]
2004 Jan 15
2
re: hardware requirement asterisk
This is ifconfig on openbsd box:
fxp0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
I think this output shows that the fxp0 interface is on simplex mode.
The voice degradation I referred was by using xlite soft phone. I open 2
line similtaneously and dial to FWD and back to my incoming extension.
Xlite is runnning on a w2k box with realtek 100M nic in auto mode. I can
2012 Sep 17
2
Constraint Optimization with constrOptim
Hi,
I am having trouble using constrOptim. My target is to do a portfolio optimization and there some constraints have to be fulfilled.
1) The weight of each share of the portfolio has to be greater than 0
2) The sum of these weights has to be 1
I am able to fulfill either the first or the second constraint but not both.
One simple way would be to fulfill the first constraint by using optim as
2008 May 28
3
7-STABLE: bridge and em
Hello list!
When em0 has an inet address while bridge0 doesn't, it seems to be OK:
-----
bs1% uname -a
FreeBSD bs1.sp34.ru 7.0-STABLE FreeBSD 7.0-STABLE #0: Sun May 25 20:15:26 MSD 2008 root@bs1.sp34.ru:/usr/obj/usr/src/sys/BSM i386
bs1% ifconfig em0; ifconfig tap0; ifconfig bridge0
em0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> metric 0 mtu 1500