similar to: Algorithm needed

Displaying 20 results from an estimated 4000 matches similar to: "Algorithm needed"

2012 Nov 14
5
aggregate combination data
Dear R users, I want to aggregate all *d *data from all combination of n *plots* taken by k. Thank very much! My data is like that: plot d 1 14 1 13 1 12 1 14 1 18 1 20 1 21 1 43 1 108 1 43 2 41 2 61 2 83 2 61 2 84 2 45 2 21 2 12 2 11 ... 100 10 100 12 -- --- Catalin-Constantin ROIBU Forestry engineer, PhD Forestry Faculty of Suceava
2013 Jan 24
2
Please help R error message "masked from 'package:utils':combn"
Hi The message occurred from R, when I was selected of "optimization > block diagonal Fhiser matrix" and used the attached file on PFIM. Could you please advise me about the following message? ***************************** Loading required pakage: combinat Attaching package:'combinat' The following object(s) are masked from 'package:utils':combn
2013 Sep 06
1
Importing function that is previously imported by other package
Dear developeRs, I encounter the following problem: in the current version of my package FrF2, certain calls to a functioni do not work when package combinat is loaded, because function combn from combinat masks the function from utils that my package uses. I tried to solve this issue by importing function combn into the namespace of FrF2; I don't need to export it, I just want to use it
2006 May 08
3
Non repetitive permutations/combinations of elements
Hello all, I am trying to create a matrix of 1s and -1s without any repetitions for a specified number of columns. e.g. 1s and -1s for 3 columns can be done uniquely in 2^3 ways. -1 -1 -1 -1 -1 1 -1 1 -1 -1 1 1 1 -1 -1 1 -1 1 1 1 -1 1 1 1 and for 4 columns in 2^4 ways and so on. I finally used the function combn([0 1],3) that I found at the following link
2005 Aug 17
2
Copying rows from a matrix using a vector of indices
Hi, I am trying to use a vector of indices to select some rows from a matrix. But before I can do that I somehow need to convert 'combinations' into a list, since 'mode(combinations)' says it's 'numerical'. Any idea how I can do that? library("combinat") combinations <- t(combn(8,2)) indices <- c(sample(1:length(combinations),10)) # convert ???
2012 Jun 08
1
Saving estimates after nested loops
 Hi R-listers, Savings regression results after a loop is straightforward. But what about when you have nested loops? I am running a regression of the form  lm(y~1+x+M+ D[,i] + D[,j] + D[,k]) where x is the variable of interest. M and D are vectors with other covariates. Vectors "M" and "x" are included in every regression. Then i loop over the columns of D to use all
2005 Dec 08
1
Listing all possible samples of size n form a population of size N
Dear useRs! I would like to list all possible samples of size n form a population of size N. Obviously, N must be small (up to 20??) for this to be possible. For example, let say that N = 3 and n = 2. Therefore, we can say we have units 1, 2 and 3. I believe all possible samples are : {1,2},{2,3} and {1,3}. I would like to emphasize that I am not looking for the number of different
2010 Nov 25
2
delete-d jackknife
Hi dear all, Can aynone help me about delete-d jackknife usually normal jackknife code for my data is: n <- nrow(data) y <- data$y z <- data$z theta.hat <- mean(y) / mean(z) print (theta.hat) theta.jack <- numeric(n) for (i in 1:n) theta.jack[i] <- mean(y[-i]) / mean(z[-i]) bias <- (n - 1) * (mean(theta.jack) - theta.hat) print(bias) but how i can apply delete-d jackknife
2017 Nov 01
2
"prob" package alternative
The prob package has been archived because it depends upon some other packages which have issues. However, such projects as Introduction to Probability and Statistics in R depend upon it for learning. There are a few other resources that also use it. Does anyone know of any workarounds? Someone at stack exchange mentioned using R 2.9. However, that broke my RStudio (WSOD) and the dependent
2011 Jul 07
2
elimination duplicate elements sampling!
Hi everyone! I have a data frame with 1112 time series and I am going to randomly sampling r samples for z times to compose different portfolio size(r securities portfolio). As for r=2 and z=10000,that's: z=10000 A=seq(1:1112) x1=sample(A,z,replace =TRUE) x2=sample(A,z,replace =TRUE) M=cbind(x1,x2) # combination of 2 series Because in a portfolio with x1[i]=x2[i],(i=1,2,...,10000) means a 1
2006 Jul 13
1
looping using combinatorics
I have a problem where I need to loop over the total combinations of vectors (combined once chosen via combinatorics). Here is a simplification of the problem: STEP 1: Define three vectors a, b, c. STEP 2: Combine all possible pairwise vectors (i.e., 3 choose 2 = 3 possible pairs of vectors: ab,ac, bc) NOTE: the actual problem has 8 choose 4, 8 choose 5 and 8 choose 6 combinations. STEP
2015 Mar 21
3
Combinatoria
Hola buenos días, me presento, me llamo Miguel y 'soy de' y 'vivo en' Galicia. Soy profesor de secundaria (Bachillerato Adultos) y llevo 15 días estudiando R a un buen ritmo, pero todavía me faltan miles de cosas. He visto que R facilita, no solo el análisis de datos y que posee una potencia en cálculos estadísticos a cualquier nivel, sino gran caudal de recursos para Data Mining,
2006 Oct 06
1
Sum of Bernoullis with varying probabilities
Hi Folks, Given a series of n independent Bernoulli trials with outcomes Yi (i=1...n) and Prob[Yi = 1] = Pi, I want P = Prob[sum(Yi) = r] (r = 0,1,...,n) I can certainly find a way to do it: Let p be the vector c(P1,P2,...,Pn). The cases r=0 and r=n are trivial (and also are exceptions for the following routine). For a given value of r in (1:(n-1)), library(combinat) Set <- (1:n)
2015 Mar 21
4
Combinatoria
En relación con lo que comenta Carlos, por ejemplo para el caso de las Variaciones sin Repetición, puede ser instructivoenseñar como se construye como por ejemplo: VsinR <- function(m, n){ return (factorial(m)/factorial(m-n))} VsinR(9,3) ------------------------- Creo que con la función factorial que viene por defecto en R puedes construir siguiendo este modelo rápidadmentecasi cualquier
2008 Jul 03
1
Problem in applying conditional looping
Respected All, I hope you are enjoying good health, I am tring to write a program in R but could not be very sucessful. My program draws random sample form bivariate normal distribution and then compute a variable PIJ. For certian samples some entries of variable PIJ is apearing as negative, which result in negative variance estimator. I want to introduce a loop in my program that verify the each
2017 Nov 02
2
"prob" package alternative
The issue is fAsianOptions. Is there a version that works with the latest version of R? If not, which version of it works with which version of R and where can it be found? I tried several at the archive already. Alternatively, is there another package that behaves similarly to prob? On Wed, Nov 1, 2017 at 6:17 PM, David Winsemius <dwinsemius at comcast.net> wrote: > > > On Nov
2006 Jan 30
2
yet another vectorization question
Dear R-helpers, I'm trying to develop a function which specifies all possible expressions that can be formed using a certain number of variables. For example, with three variables A, B and C we can have - presence/absence of A; B and C - presence/absence of combinations of two of them - presence/absence of all three A B C 1 0 2 1 3 0 4 1 5 0 6 1
2007 Jul 16
5
formula(CO2)
The formula attribute of the builtin CO2 dataset seems a bit strange: > formula(CO2) Plant ~ Type + Treatment + conc + uptake What is one supposed to do with that? Certainly its not suitable for input to lm and none of the examples in ?CO2 use the above.
2015 Mar 22
3
Combinatoria
Hola amigos, muchas gracias por vuestra ayuda. Entonces veo que mi sorpresa era legítima. Por todos vuestros mails la conclusión es que: - En el módulo base de R no incluye combinatoria elemental, ni siquiera el número combinatorio Cm,n hay que cargar el paquete *combinat* - Y para las variaciones con repetición el paquete* gtools* - Y aún así no tenemos ni las combinaciones ni las
2015 Mar 22
2
Combinatoria
Hola Miguel, Sí se pueden obtener las variaciones con y sin repetición en R. Eso sí están un poco escondidas... Se pueden calcular de esta forma: #---------------------- > #Cargar el paquete gtools > library(gtools) > #Definir el conjunto sobre el que se hará el cálculo > x <- c('rojo', 'azul', 'verde') > #Utilizar la función "permutations()"