search for: maxima

I''m looking to write a javascript heavy clientside program with a something serverside backend that connects to the free maxima math program. I have extensive knowledge of ruby on rails, so I would prefer to call Maxima with ruby, but I don''t know if this is even possible. Its fairly easy to call Maxima (with a lisp implementation) using ANSI C, it is a little less easy to implement using JAVA with a lisp implement...

Hello, I'm aware that recently there has been discussion of R joining forces with an algebra system in some way. Here is my $0.02. I suggest linking R with Maxima (http://maxima.sf.net). Maxima is written in Lisp. Maxima objects are pretty simple. Maxima works on expressions, and almost every expression is a Lisp list of the form ((op) arg1 arg2 arg3 ...) which associates an operator and its arguments. Every kind of operation is cast in this form -- infix,...

What is 1. par.ests <- optimfit$par 2. fisher <- hessb(negloglik, par.ests, maxvalue=maxima); 3. varcov <- solve(fisher); 4. par.ses <- sqrt(diag(varcov)); Thanks a lot, fit.GEV <- function(maxima) { sigma0 <- sqrt((6. * var(maxima))/pi) mu0 <- mean(maxima) - 0.57722 * sigma0 xi0 <- 0.1 theta <- c(xi0, mu0, sigma0) #10/5/2007: removed assign() for maxima.nl #10/5/2...

If a run a LOESS model and then produce a smoothed surface: Is there any way to determine the coordinates of the local maxima on the surface? [[alternative HTML version deleted]]

...mixCoeff=mc0/sum(mc0)) > > plot(rv, to.draw.arg="d") > > > I am getting 731.1345 from the code you have provide > > > It is part of a code, so it was difficult to write a reproducible code > > I have tried to use optimr but it gives me the local maxima, now I am > struck with the problem of how to get the global maxima > This is basically an optimization problem so it?s nothing to do with distr package and UnivarMixingDistribution function. Also I?m not able to install distr package because of an error. Can you create an example by rnorm...

...Norm(819.2011, 57.06655), mixCoeff=mc0/sum(mc0)) plot(rv, to.draw.arg="d") I am getting 731.1345 from the code you have provide It is part of a code, so it was difficult to write a reproducible code I have tried to use optimr but it gives me the local maxima, now I am struck with the problem of how to get the global maxima On Sat, Aug 26, 2017 at 3:12 PM, Ismail SEZEN [via R] < ml+s789695n4744993h60 at n4.nabble.com> wrote: > > > On 26 Aug 2017, at 14:18, Ulrik Stervbo <[hidden email] > <http:///user/SendEmail.jtp?type=node&a...

Hi I have a large dataset which follows a multimodal distribution. And I would like to identify the maxima. As the data is obtained from a stochastic simulation, not all maxima in the data are "real maxima of the dirstribution" but rather small random fluctuations. Unfortunately, it is not possible for me to run more simulations to smooth the obtained distribution. What I am doing at the...

---------- Forwarded message ---------- From: niharika singhal <niharikasinghal1990 at gmail.com> Date: Sun, Aug 27, 2017 at 11:57 AM Subject: Re: Find maxima of a function To: "David Winsemius [via R]" <ml+s789695n4745009h56 at n4.nabble.com>, "Ismail SEZEN [via R]" <ml+s789695n4744993h60 at n4.nabble.com>, Ulrik Stervbo <ulrik.stervbo at gmail.com> Dear David and Ismail, The actual problem is I am getting the pa...

Dear all, suppose I have a bi-variate function f(x,y), I want to find the maxima. I define x and y vector, and get matrix z=f(x,y). how can I get which (x0,y0) makes z become the maxima? I can do two loops to get the x0 and y0, but I think there may exist a function to do this.

Dear all, I wonder which R algorithm could perform a search of local maxima in an spatial grid, in other words, having the coordinates of a map (x,y,z... up to 6 coordinates) and then the altitude/height at each point (h) (in total 7 numerical variables) I would like to localise the peaks (local maxima) of that topological surface. Which R algorithm can perform this? Than...

...solate the problematic part from the rest of your study. Sometimes, more information does not help to solution. All the answers from us (Ulrik, David, me) are more or less are correct to find a maximum point. Newton?s method is also correct. But after answers, you only say, it didn?t find the right maxima. At this point I?m cluesless, because problem might be originated at some other point and we don?t know it. For instance, In my previous answer, my suggested solution was right for both your 2 situations. But suddenly you just said, it didin?t work for a mean greater than 6 and I?m not able to repr...

...disjoint, contiguous subvectors. For example, let v = c(1,4,2,6,7,5), partition it into three subvectors, v1 = v[1:3], v2 = v[4], v3 = v[5:6]. I want to find the maximum element of each subvector. In this example, max(v1) is 4, max(v2) is 6, max(v3) is 7. If I knew that the successive subvector maxima would never decrease, as in the example, I could do the following: partiCmax <- function( values, seriesIdx ) { # assume seriesIdx is increasing integer sequence beginning with 1, ending at less than or equal to length(values) parti <- cbind( seriesIdx, c( ( seriesIdx[ -1 ] - 1 ), lengt...

...bit. I am not sure whether the bugs is in compiz or somewhere else so it would be nice if someone could confirm them. Here they are: - on default window decoration the maximize and minimize buttons have an unwanted black decoration on mouse over. Screenshots: http://img.photobucket.com/albums/v27/maxima/Compiz/maximize.jpg http://img.photobucket.com/albums/v27/maxima/Compiz/minimize.jpg - double clicking on titlebar sometimes put window at weird state (see screenshot), single click anywhere put window on maximize state. http://img.photobucket.com/albums/v27/maxima/Compiz/epiphany.png I tried it w...

...solate the problematic part from the rest of your study. Sometimes, more information does not help to solution. All the answers from us (Ulrik, David, me) are more or less are correct to find a maximum point. Newton?s method is also correct. But after answers, you only say, it didn?t find the right maxima. At this point I?m cluesless, because problem might be originated at some other point and we don?t know it. For instance, In my previous answer, my suggested solution was right for both your 2 situations. But suddenly you just said, it didin?t work for a mean greater than 6 and I?m not able to repr...

>From time to time people request symbolic computations beyond what D() and deriv() etc can provide. A brief look at the internet shows that there are many more or less developed computer algebra packages freely available. Therefore, I wondered if it would be an idea to try to 'integrate' one of these packages in R, which I guess can be done in more or less elegant ways... I do not know

I have data in the form of (x,y) pairs and would like to find local minima and maxima (typically the zeros of the 2nd derivative) of the y values. I looked at numericDeriv, but I don't have an "expression" per se. I looked at optim, also, but it looks like it will find only one "global" max or min. I can code up my own piecewise derivatives, but wonder...

Hi there, I use the surf.gls() function to fit a variable measured over a surface. When I plot the predicted surface, there are local minima/maxima in almost every coordinate where data were measured, which seems aberrant. For instance: ?? x <- c(343,293,343,243,293,343,443,543,593,243,293,343,393,443,493,543,593,143,193,243,293,343,393,443, 493,543,593,193,243,293,343,543,593,643,93,193,243,293,343,393,443,493,543,43,93,143,193,243,293,...

...mage description here] <https://i.stack.imgur.com/4uUQ9.png> Also, if I change my parameters to mean=(2.15,2.0,2.9) sigma=(0.1,0.1,0.1) c=(1/3,1/3,1/3) Then plot would change to[image: enter image description here] <https://i.stack.imgur.com/kESYX.png> Is there any way to find the maxima. I have tried Newton's method but it gave me the wrong output. Like in general some common solution, which would work on all the cases, is needed.Can someone suggest me how can I achieve this Thanks in advance Niharika Singhal [[alternative HTML version deleted]]

...rik On Sa., 26. Aug. 2017, 12:57 niharika singhal <niharikasinghal1990 at gmail.com> wrote: > Hi > > Thanks for you mail, > I really appreciate your time on my problem > > I have posted this problem on > > > https://stats.stackexchange.com/questions/299590/to-find-maxima-for-gaussian-mixture-model > > > The plot I am getting using UnivarMixingDistribution from distr package in > R > > code is > > mc0= c(0.1241933, 0.6329082 <06329%20082>, 0.2428986 <02428%20986>) > rv > <-UnivarMixingDistribution(Norm(506.8644,61.02859),...

Dear R users, I have created a Loess surface in R, in which x is relative longitude by miles, y is relative latitude by miles, and z is population density at the neighborhood level. The purpose is to identify some population centers in the region. I'm wondering if there is a way to determine the coordinates (x,y) of each center, so I can know exactly where they are. Let me use the