Re: [R] Optimize code to read text-file with digits

2017-09-08 Thread William Dunlap via R-help
Remove the for loop and all the [i]'s in your code and it will probably go faster. I.e., change f0 <- function (lines) { numbers <- vector("numeric") for (i in 1:length(lines)) { lines[i] <- sub("[^ ]+ +", "", lines[i]) lines[i] <- gsub(" ", "", lines[i]) numbers <

Re: [R] Optimize code to read text-file with digits

2017-09-08 Thread Martin Maechler
> peter dalgaard > on Fri, 8 Sep 2017 16:12:21 +0200 writes: >> On 8 Sep 2017, at 15:51 , Martin Møller Skarbiniks >> Pedersen wrote: >> >> On 8 September 2017 at 14:37, peter dalgaard >> wrote: >>> >>> On 8 Sep 2017, at 14:03 , peter dalgaard

Re: [R] Optimize code to read text-file with digits

2017-09-08 Thread peter dalgaard
> On 8 Sep 2017, at 15:51 , Martin Møller Skarbiniks Pedersen > wrote: > > On 8 September 2017 at 14:37, peter dalgaard wrote: >> >> >>> On 8 Sep 2017, at 14:03 , peter dalgaard wrote: >>> >>> x <- scan("~/Downloads/digits.txt") >>> x <- x[-seq(1,22,11)] >> >> ...and, come to think of

Re: [R] Optimize code to read text-file with digits

2017-09-08 Thread Martin Møller Skarbiniks Pedersen
On 8 September 2017 at 14:37, peter dalgaard wrote: > > > > On 8 Sep 2017, at 14:03 , peter dalgaard wrote: > > > > x <- scan("~/Downloads/digits.txt") > > x <- x[-seq(1,22,11)] > > ...and, come to think of it, if you really want the 100 random digits: > > xx <- c(outer(x,10^(0:4), "%/%")

Re: [R] Optimize code to read text-file with digits

2017-09-08 Thread peter dalgaard
> On 8 Sep 2017, at 14:03 , peter dalgaard wrote: > > x <- scan("~/Downloads/digits.txt") > x <- x[-seq(1,22,11)] ...and, come to think of it, if you really want the 100 random digits: xx <- c(outer(x,10^(0:4), "%/%")) %% 10 -- Peter Dalgaard, Professor, Center for Statistics, Copen

Re: [R] Optimize code to read text-file with digits

2017-09-08 Thread PIKAL Petr
Hi see in line > -Original Message- > From: R-help [mailto:r-help-boun...@r-project.org] On Behalf Of Martin > Moller Skarbiniks Pedersen > Sent: Friday, September 8, 2017 11:58 AM > To: r-help@r-project.org > Subject: Re: [R] Optimize code to read text-file wi

Re: [R] Optimize code to read text-file with digits

2017-09-08 Thread peter dalgaard
Simplest version that I can think of: x <- scan("~/Downloads/digits.txt") x <- x[-seq(1,22,11)] length(x) # 20 hist(x) Now, because it's Friday: How does one work out the theoretical distribution of the following table? > table(table(factor(x,levels=0:9))) 0 1 2 3

Re: [R] Optimize code to read text-file with digits

2017-09-08 Thread Martin Møller Skarbiniks Pedersen
On 8 September 2017 at 11:25, PIKAL Petr wrote: > > Moller Skarbiniks Pedersen > My program which is slow looks like this: > > > > filename <- "digits.txt" > > lines <- readLines(filename) > > why you do not read a file as a whole e.g. by > > lines<-read.table("digits.txt") > Good idea. > > An

Re: [R] Optimize code to read text-file with digits

2017-09-08 Thread PIKAL Petr
Hi see in line > -Original Message- > From: R-help [mailto:r-help-boun...@r-project.org] On Behalf Of Martin > Moller Skarbiniks Pedersen > Sent: Friday, September 8, 2017 10:49 AM > To: r-help@r-project.org > Subject: [R] Optimize code to read text-file with digits &

[R] Optimize code to read text-file with digits

2017-09-08 Thread Martin Møller Skarbiniks Pedersen
Hi, Every day I try to write some small R programs to improve my R-skills. Yesterday I wrote a small program to read the digits from "A Million Random Digits" from RAND. My code works but it is very slow and I guess the code is not optimal. The digits.txt file downloaded from https://www.ra

Re: [R] Optimize selected variables but not all - nloptr

2016-10-20 Thread ProfJCNash
optimr/optimrx are for unconstrained and bounds constrained problems. I think you are going to have to do the masking yourself. It's more messy and tedious than difficult. The optimization is on a new set of parameters newpar that has fewer components, so in your objective function and constraint

Re: [R] Optimize selected variables but not all - nloptr

2016-10-20 Thread Narendra Modi
Thanks Prof Nash. The reason I used nlopr() in my problem is due to non linear constraints. I wonder if optimrx/optim can model the below scenario. I will be elated if it can. The problem in hand goes like this: There are 2 injectors and 2 producers. Consider these as some entity. I have an actua

Re: [R] Optimize selected variables but not all - nloptr

2016-10-19 Thread ProfJCNash
I refer to such parameters as "masked" in my 2014 book Nonlinear parameter optimization with R tools. Recently I put package optimrx on R-forge (and optimr with fewer solvers on CRAN) that allows for masks with all the parameters. The masks can be specified as you suggest with start=lower=upper.

Re: [R] Optimize selected variables but not all - nloptr

2016-10-19 Thread Jeff Newmiller
You provided the data but not the broken code. -- Sent from my phone. Please excuse my brevity. On October 19, 2016 2:59:08 PM PDT, Narendra Modi wrote: >Hello All, >I have a matrix with initial values as below and I need to optimize >the variables that are greater than 0. > > TAU

[R] Optimize selected variables but not all - nloptr

2016-10-19 Thread Narendra Modi
Hello All, I have a matrix with initial values as below and I need to optimize the variables that are greater than 0. TAU fij fij2 [1,] 14.33375 0.000 0.01449572 [2,] 14.33375 0.000 0. [3,] 14.33375 0.000 0. [4,] 14.33375 0.000 0.02206446 [

Re: [R] optimize the filling of a diagonal matrix (two for loops)

2016-08-18 Thread Thomas Mailund
  The nested for-loops could very easily be moved to Rcpp which should speed them up. Using apply functions instead of for-loops will not make it faster; they still have to do the same looping. At least, when I use `outer` to replace the loop I get roughly the same speed for the two versions —

[R] optimize the filling of a diagonal matrix (two for loops)

2016-08-18 Thread AURORA GONZALEZ VIDAL
Hello I have two for loops that I am trying to optimize... I looked for vectorization or for using some funcions of the apply family  but really cannot do it. I am writting my code with some small data set. With this size there is no problem but sometimes I will have hundreds of rows so it is real

[R] RSM in R, optimize/minimize a response

2015-10-07 Thread simon.heintz
1.12329 0.68861 1.23011 1.49413 0.01698659 ... 11 ... ... 2150... ... 55999 1.19111 1.48329 0.8806591.82682 0.037803564 56000 1.11901 1.12973 0.5230261.92828 0.038733914 -- View this message in context: http://r.789695.n4.nabble.com/RSM-in-R-optimize-minimize-a-response-tp47

Re: [R] optimize

2014-10-01 Thread peter dalgaard
Yup. And books don't rewrite themselves when the software changes, so if things don't seem to work, check the _current_ documentation. -pd On 01 Oct 2014, at 21:53 , William Dunlap wrote: > Change your 'max=T' to 'maximum=TRUE'. A long time ago the '...' in > optimize's argument > list was a

Re: [R] optimize

2014-10-01 Thread William Dunlap
Change your 'max=T' to 'maximum=TRUE'. A long time ago the '...' in optimize's argument list was at the end, so you could abbreviate any of its argument names. Now the '...' is the third formal argument, so all the trailing arguments meant for optimize itself must be fully spelled out. Otherwise

[R] optimize

2014-10-01 Thread Nick gayeski
Page 53 of Robert and Casella's "Use R" book, Introduction to Monte Carlo Methods with R, has the following code: optimize(f=function(x){dbeta(x,2.7,6.3)}, + interval=c(0,1) ,max=T)$objective This should return [1] 2.669744 I run R from R Studio. When I enter this code I receive the

Re: [R] Optimize function in R: unable to find maximum of logistic function

2013-10-28 Thread Shantanu MULLICK
Hello, Thanks a lot for the replies. I tried to use the "optim" function in R, and chose the "L-BFGS-B" method of optimization. Now the result is very sensitive to the starting values. I use the same function, but I give the line of code I use for "optim". optim(0.25, f, method= "L-BFGS-B", low

Re: [R] Optimize function in R: unable to find maximum of logistic function

2013-10-28 Thread William Dunlap
lap tibco.com > -Original Message- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On > Behalf > Of William Dunlap > Sent: Monday, October 28, 2013 3:03 PM > To: Rolf Turner; Shantanu MULLICK > Cc: r-help@r-project.org > Subject: Re: [R] O

Re: [R] Optimize function in R: unable to find maximum of logistic function

2013-10-28 Thread William Dunlap
n, with its log=TRUE and perhaps lower.tail=FALSE arguments. Bill Dunlap Spotfire, TIBCO Software wdunlap tibco.com > -Original Message- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On > Behalf > Of Rolf Turner > Sent: Monday, October 28

Re: [R] Optimize function in R: unable to find maximum of logistic function

2013-10-28 Thread Rolf Turner
This could be described as a bug, perhaps. Or it could be described as an indication that numerical optimization is inevitably tricky. Notice that if you narrow down your search interval from [0,5] to [0,0.5] you get the right answer: > optimize(f, c(0, 0.5), maximum= TRUE,tol=1e-10) $maximum [

Re: [R] Optimize function in R: unable to find maximum of logistic function

2013-10-28 Thread Rui Barradas
Hello, This seems like a bug, removing 'maximum = TRUE' has no effect except that the returned value says it's a minimum, not a maximum. Rui Barradas Em 28-10-2013 17:00, Shantanu MULLICK escreveu: Hello Everyone, I want to perform a 1-D optimization by using the optimize() function. I want

[R] Optimize function in R: unable to find maximum of logistic function

2013-10-28 Thread Shantanu MULLICK
Hello Everyone, I want to perform a 1-D optimization by using the optimize() function. I want to find the maximum value of a "logistic" function. The optimize() function gives the wrong result. My code: f= function (k) { T_s = 20 result = (2- 2/(1+ exp(-2*T_s*k))) return(result) } optimize(f, c(0

Re: [R] optimize integer function parameters

2013-07-23 Thread Enrico Schumann
On Tue, 23 Jul 2013, Christof Kluß writes: > Am 23-07-2013 13:20, schrieb Enrico Schumann: > >> On Tue, 23 Jul 2013, Christof Kluß writes: >> >>> >>> I have "observations" obs <- (11455, 11536, 11582, 11825, 11900, ...) >>> >>> and a simulation function f(A,B,C,D,E,F), so sim <- f(A,B,C,D,E,F)

Re: [R] optimize integer function parameters

2013-07-23 Thread Christof Kluß
Hi the integer values in the vectors sim and obs are dates when I set sim <- f(TS0,TS1,TS2,TB0,TB1,TB2) my A,..,F below then TS0 and TB0 are depend (and so on) the main thing in f(...) is something like for (i in c(1:length(temperature))) { Temp <- temperature[i] if (DS < 0) {

Re: [R] optimize integer function parameters

2013-07-23 Thread Enrico Schumann
On Tue, 23 Jul 2013, Christof Kluß writes: > > I have "observations" obs <- (11455, 11536, 11582, 11825, 11900, ...) > > and a simulation function f(A,B,C,D,E,F), so sim <- f(A,B,C,D,E,F) > > e.g. sim = c(11464, 11554, 11603, 11831, 11907, ...) > > now I would like to fit A,B,C,D,E,F such that "

[R] optimize integer function parameters

2013-07-22 Thread Christof Kluß
Hi I have "observations" obs <- (11455, 11536, 11582, 11825, 11900, ...) and a simulation function f(A,B,C,D,E,F), so sim <- f(A,B,C,D,E,F) e.g. sim = c(11464, 11554, 11603, 11831, 11907, ...) now I would like to fit A,B,C,D,E,F such that "obs" and f(A,B,C,D,E,F) match as well as possible. A

[R] optimize and mcparallel problem

2012-10-03 Thread Matthew Wolak
Dear list, I am running into 2 problems when using the optimize function from the stats package (note: I've also tried unsuccessfully to use optim, nlm, & nlminb). The second problem is caused by my solution to the first, so I am asking if anyone has a better solution to the first question, or i

Re: [R] Optimize a function with Discrete inputs

2012-08-02 Thread R. Michael Weylandt
On Thu, Aug 2, 2012 at 5:58 AM, loyolite270 wrote: > oh sorry .. > > The detailed description of the problem is given below > > dataFrame is matrix of dim 100X100 with some values Odd name for something that's not a dataFrame (i.e., data.frame != matrix) > a is a vector of length 1 > x is a

Re: [R] Optimize a function with Discrete inputs

2012-08-02 Thread loyolite270
oh sorry .. The detailed description of the problem is given below dataFrame is matrix of dim 100X100 with some values a is a vector of length 1 x is a vector of any length between 1 to 99 funcScore<-function(a,x){ sc<-0 sc1<-0 for(j in 1:(length(x))){ sc<-sc+abs(d

Re: [R] Optimize a function with Discrete inputs

2012-08-01 Thread R. Michael Weylandt
You'll have to give a more realistic description to get detailed help: otherwise, look up "combinatorial optimization" and "parallelization" for some generic pointers. Best, Michael On Wed, Aug 1, 2012 at 11:34 AM, loyolite270 wrote: > Thanks for the reply, but the example i have given above is

Re: [R] Optimize a function with Discrete inputs

2012-08-01 Thread loyolite270
Thanks for the reply, but the example i have given above is a sample function. I would be using a function with input vector of size more than 100 and the function will compute some score based on the 100 vector combinations. Since i don't want to do this computation sequentially for all these com

Re: [R] Optimize a function with Discrete inputs

2012-08-01 Thread peter dalgaard
On Aug 1, 2012, at 16:34 , Sarah Goslee wrote: > combn() gives ordered combinations, while expand.grid() gives all > combinations. ...and there's one more function that is designed to tabulate a function of two variables over a grid. And yet another one to find which value is max in an array

Re: [R] Optimize a function with Discrete inputs

2012-08-01 Thread Sarah Goslee
combn() gives ordered combinations, while expand.grid() gives all combinations. I'd give worked code but this hints at homework to me. Sarah On Wed, Aug 1, 2012 at 10:23 AM, Eik Vettorazzi wrote: > Hi, > not sure if that is what you are looking for, but have a look at > > cmb<-t(combn(c(0,3,5,8

Re: [R] Optimize a function with Discrete inputs

2012-08-01 Thread Eik Vettorazzi
Hi, not sure if that is what you are looking for, but have a look at cmb<-t(combn(c(0,3,5,8),2)) #get all pairs of combinations cbind(cmb,apply(cmb,1,diff)) #for each pair, get the difference cheers Am 01.08.2012 12:29, schrieb loyolite270: > Hi > > I need to optimize the below function: >

[R] Optimize a function with Discrete inputs

2012-08-01 Thread loyolite270
Hi I need to optimize the below function: a=function(x){ A=x[1] B=x[2] C=B-A return(C) } I need to optimize the above function such that x can be any combination of these number (0,3,5,8) of vector length 2 (i.e) x can be (3,0), (5,0), (8,0), (3,5), (3,8), (5,8), .. etc can s

Re: [R] optimize()

2011-12-13 Thread dnz.marcio
Wow...it's so simple! I have specified the variable times. Thank you so much, Ben! -- View this message in context: http://r.789695.n4.nabble.com/optimize-tp4173920p4192278.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-pro

Re: [R] optimize()

2011-12-09 Thread Ben Bolker
dnz.marcio gmail.com> writes: > [snip] > # Logaritmo da distribuição condicional de alpha[i] > > lp_alphai <- function(alphai, i, beta, tau, N){ > > t1 <- (N[i+1] - N[i])*log(alphai) > t2 <- - (N[i+1] - N[i])*alphai*log(beta[i]) > t3 <- (alphai - 1)*sum(log(times[(N[i] + 1):N[i+1]])) >

[R] optimize()

2011-12-08 Thread dnz.marcio
Hi! I have a difficulty in the use of function optimize(). Could you help me? I want to maximize this function: # Logaritmo da distribuição condicional de alpha[i] lp_alphai <- function(alphai, i, beta, tau, N){ t1 <- (N[i+1] - N[i])*log(alphai) t2 <- - (N[i+1] - N[i])*alphai*log(beta[i])

Re: [R] optimize R code: replace for loop

2011-10-05 Thread Albert-Jan Roskam
quot; >Sent: Wednesday, October 5, 2011 11:54 AM >Subject: Re: [R] optimize R code: replace for loop > >You can vectorize it using cumsum. > >cumsum(c(1, testvec)) > >all.equal(final.sum, cumsum(c(1, testvec))) > >> -Oorspronkelijk bericht- >> Van: r-h

Re: [R] optimize R code: replace for loop

2011-10-05 Thread ONKELINX, Thierry
; Aan: r-help@r-project.org > Onderwerp: [R] optimize R code: replace for loop > > Dear R Users, > > at the moment I am trying to optimize an R script. > > testvec <- c(0,1,0,1,1,1,1,0,0,1,0,1,0) > > > sum.testvec <- vector() > tempsum <- 1 > for (e

[R] optimize R code: replace for loop

2011-10-05 Thread Chris82
Dear R Users, at the moment I am trying to optimize an R script. testvec <- c(0,1,0,1,1,1,1,0,0,1,0,1,0) sum.testvec <- vector() tempsum <- 1 for (e in 1:length(testvec)){ sum.testvec[e] <- tempsum+testvec[e] tempsum <- sum.testvec[e] } final.sum <- c(1,sum.testvec) Is there an option to do

[R] optimize weights for a weighted average?

2011-06-20 Thread Seth
Hi, I have a simple problem where I have two or more predictor variables that range from 0 to 1 and binary response variable (0 or 1). In the two variable case, the model to fit with maximum likelihood would simply be: P(Y=1) = (B1*X1 + B2*X2)/(B1+B2) or if least squares is to be minimized

Re: [R] optimize

2011-01-03 Thread David Winsemius
On Jan 3, 2011, at 11:09 AM, Muhammad Rahiz wrote: Josh's recommendation to use predict works. At the same time, I'll work on your suggestions, David. Thanks. Muhammad Rahiz Researcher & DPhil Candidate (Climate Systems & Policy) School of Geography & the Environment University of Oxford O

Re: [R] optimize

2011-01-03 Thread Muhammad Rahiz
Josh's recommendation to use predict works. At the same time, I'll work on your suggestions, David. Thanks. Muhammad Rahiz Researcher & DPhil Candidate (Climate Systems & Policy) School of Geography & the Environment University of Oxford On Mon, 3 Jan 2011, David Winsemius wrote: On Jan 3,

Re: [R] optimize

2011-01-03 Thread David Winsemius
On Jan 3, 2011, at 9:52 AM, Muhammad Rahiz wrote: Hi all, I'm trying to get the value of y when x=203 by using the intersect of three curves. The horizontal curve does not meet with the other two. How can I rectify the code below? Thanks Muhammad ts <- 1:10 dd <- 10:1 ts <- seq(200,20

Re: [R] optimize

2011-01-03 Thread David Winsemius
On Jan 3, 2011, at 9:52 AM, Muhammad Rahiz wrote: Hi all, I'm trying to get the value of y when x=203 by using the intersect of three curves. The horizontal curve does not meet with the other two. How can I rectify the code below? Extend the appropriate axes. xlim and ylim are the argume

Re: [R] optimize

2011-01-03 Thread Joshua Wiley
Hi Muhammad, On Mon, Jan 3, 2011 at 6:52 AM, Muhammad Rahiz wrote: > Hi all, > > I'm trying to get the value of y when x=203 by using the intersect of three > curves. The horizontal curve does not meet with the other two. How can I > rectify the code below? What is your code supposed to do? Thi

[R] optimize

2011-01-03 Thread Muhammad Rahiz
Hi all, I'm trying to get the value of y when x=203 by using the intersect of three curves. The horizontal curve does not meet with the other two. How can I rectify the code below? Thanks Muhammad ts <- 1:10 dd <- 10:1 ts <- seq(200,209,1) dd <- c(NA,NA,NA,NA,1.87,1.83,1.86,NA,1.95,1.9

Re: [R] Optimize multiple variable sets

2010-12-06 Thread Hans W Borchers
peter dalgaard gmail.com> writes: > > On Dec 6, 2010, at 15:15 , Jonathan P Daily wrote: > > > Correct me if I'm wrong, but isn't the minimal x value in your example > > the same regardless of what positive coefficient you apply to x? If that > > is the case, you would expect the same min(x) for

Re: [R] Optimize multiple variable sets

2010-12-06 Thread Ravi Varadhan
org; sandra lag Subject: Re: [R] Optimize multiple variable sets I suppose I should have been more clear. I saw that her interval did not include the actual minimum, but I was asking if (and if, why) she was expecting the minimum x value to be different for each run. If the y value were returned t

Re: [R] Optimize multiple variable sets

2010-12-06 Thread Jonathan P Daily
uot;Is the room still a room when its empty? Does the room, the thing itself have purpose? Or do we, what's the word... imbue it." - Jubal Early, Firefly peter dalgaard wrote on 12/06/2010 09:39:43 AM: > [image removed] > > Re: [R] Optimize multiple variable

Re: [R] Optimize multiple variable sets

2010-12-06 Thread peter dalgaard
On Dec 6, 2010, at 15:15 , Jonathan P Daily wrote: > Correct me if I'm wrong, but isn't the minimal x value in your example the > same regardless of what positive coefficient you apply to x? If that is > the case, you would expect the same min(x) for each iteration. > > i.e. in the interval [0

Re: [R] Optimize multiple variable sets

2010-12-06 Thread Jonathan P Daily
the word... imbue it." - Jubal Early, Firefly r-help-boun...@r-project.org wrote on 12/06/2010 07:00:57 AM: > [image removed] > > [R] Optimize multiple variable sets > > sandra lag > > to: > > r-help > > 12/06/2010 08:54 AM > > Sent by:

[R] Optimize multiple variable sets

2010-12-06 Thread sandra lag
Hi, I usually use optimize function for ML Estimation. Now I´ve got a data frame with many sets, but I can´t save estimates each time I run the code for each data set (I´m using a for loop with my loglikelihood function and works ok but when I apply another for loop to: optimize(my.loglikeliho

Re: [R] Optimize parameters of ODE Problem which is solved numeric

2010-10-25 Thread Ravi Varadhan
equations. Ravi. -Original Message- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of Michael S. Sent: Saturday, October 23, 2010 8:06 PM To: r-help@r-project.org Subject: [R] Optimize parameters of ODE Problem which is solved numeric Hi, I have a data

[R] Optimize parameters of ODE Problem which is solved numeric

2010-10-23 Thread Michael S.
Hi, I have a data-matrix: > PID sato hrs fim health 214 3 4.376430 6.582958 5 193 6 4.361825 3.138525 6 8441 6 4.205771 3.835886 7 7525 6 4.284489 3.245139 6 6806 7 4.168926 2.821833 7 5682 7 1.788707 1.212653 7 5225 6 1.

[R] Optimize nnet() for cross-validation error

2010-04-17 Thread l00lsupra
I would run 200 iterations of nnet() such that optimization is done for 'f', where f = error_cross_validation * (error_cross_validation / error_training_set). Any guidance on how to optimize for this per-cycle dependent variable (f) is appreciated. Thank you, supra [[alternative HTML vers

[R] optimize a joint lieklihood with mle2

2010-03-24 Thread Benedikt Gehr, Institut für Evolutionsbiologie und Umweltwissenschaften
Hi I'm trying to maximize a joint likelihood of 2 likelihoods (Likelihood 1 and Likelihood 2) in mle2, where the parameters I estimate in Likelihood 2 go into the likelihood 1. In Likelihood 1 I estimate the vector logN with length 37, and for the Likelihood 2 I measure a vector s of length 8.

Re: [R] Optimize for loop / find last record for each person

2009-02-27 Thread Jorge Ivan Velez
Hi Andrew, Just remember that something was bad with the code I sent you (the same you referred to in [1]). This version runs with no problems: # Some data history_ <- data.frame(person_id=c(1,2,2),date_=c("2009-01-01","2009-02-03","2009-02-02"),x=c(0.01,0.05,0.06)) colnames(history_) <- c("perso

Re: [R] Optimize for loop / find last record for each person

2009-02-27 Thread Andrew Ziem
On Fri, Feb 27, 2009 at 2:10 PM, William Dunlap wrote: > Andrew, it makes it easier to help if you supply a typical > input and expected output along with your code.  I tried > your code with the following input: I'll be careful to avoid these mistakes. Also, I should not have used a reserved wo

Re: [R] Optimize for loop / find last record for each person

2009-02-27 Thread William Dunlap
[,"person_id"]),,drop=FALSE] history[order(history$date),,drop=FALSE] } > f2(history) person_id date 2 Mary2 7 Alex7 9Sue9 10 Joe 10 Bill Dunlap TIBCO Software Inc - Spotfire Division wdunlap tibco.com

Re: [R] Optimize for loop / find last record for each person

2009-02-27 Thread Jorge Ivan Velez
Dear Andrew: Here is another way assuming you have an order column in your history data as well as a person_id. Again, your variable of interest is x: # Some data set.seed(1) history<-data.frame( person_id=rep(1:10,each=10), record=rep(sample(10),10), x=rnorm(100)

Re: [R] Optimize for loop / find last record for each person

2009-02-27 Thread David Winsemius
"...from an SQL database."How? Structure of the result? You say "ordered by date" but then you don't reference any date variable? And your code creates an "order" column, but that would not appear necessary for the stated purpose and you don't output the last "order" within a "person_i

Re: [R] Optimize for loop / find last record for each person

2009-02-27 Thread Jorge Ivan Velez
Dear Andrew, Here is one way: # Some data set.seed(1) mydata<-data.frame(person_id=rep(1:10,10),x=rnorm(100)) mydata # last register for person_id with(mydata,tapply(x,person_id,function(x) tail(x,1))) # test for person_id=1 mydata[mydata$person_id==1,] # see the last number in column 2 HTH,

[R] Optimize for loop / find last record for each person

2009-02-27 Thread Andrew Ziem
I want to find the last record for each person_id in a data frame (from a SQL database) ordered by date. Is there a better way than this for loop? for (i in 2:length(history[,1])) { if (history[i, "person_id"] == history[i - 1, "person_id"]) history[i, "order"] = history[i - 1, "order"]

Re: [R] optimize simultaneously two binomials inequalities using nlm( ) or optim( )

2008-08-06 Thread Emir Toktar
. EToktar > -Original Message- > From: Marc Schwartz [mailto:[EMAIL PROTECTED] > Sent: Tuesday, August 05, 2008 1:12 PM > To: Spencer Graves > Cc: [EMAIL PROTECTED]; r-help@r-project.org > Subject: Re: [R] optimize simultaneously two binomials > inequalities using nlm(

Re: [R] optimize simultaneously two binomials inequalities using nlm( ) or optim( )

2008-08-06 Thread Emir Toktar
Thanks Mr. Graves for your support. > I saw your post on 7/29, and I have not seen a reply, > so I will attempt a response to the question at the start of > your email: > > obtain the smallest value of 'n' (sample size) satisfying > both inequalities: > > (1-alpha)

Re: [R] optimize simultaneously two binomials inequalities using nlm( ) or optim( )

2008-08-05 Thread Marc Schwartz
Just a quick follow up to Spencer's post, you might want to look at the AcceptanceSampling package on CRAN: http://cran.r-project.org/web/packages/AcceptanceSampling/index.html HTH, Marc Schwartz on 08/05/2008 09:00 AM Spencer Graves wrote: I saw your post on 7/29, and I have not seen a

Re: [R] optimize simultaneously two binomials inequalities using nlm( ) or optim( )

2008-08-05 Thread Spencer Graves
I saw your post on 7/29, and I have not seen a reply, so I will attempt a response to the question at the start of your email: obtain the smallest value of 'n' (sample size) satisfying both inequalities: (1-alpha) <= pbinom(c, n, p1) && pbinom(c, n, p2) <= beta, where alpha, p1,

[R] optimize simultaneously two binomials inequalities using nlm( ) or optim( )

2008-08-04 Thread emir.toktar
Dear R users, I´m trying to optimize simultaneously two binomials inequalities (used in acceptance sampling) which are nonlinear solution, so there is no simple direct solution. Please, let me explain shortly the the problem and the question as following. The objective is to obtain the smallest v

[R] optimize simultaneously two binomials inequalities using nlm

2008-07-29 Thread emir.toktar
Dear R users, I´m trying to optimize simultaneously two binomials inequalities used to acceptance sampling, which are nonlinear solution, so there is no simple direct solution. Please, let me explain shortly the the problem and the question as following. The objective is to obtain the smallest v

[R] optimize function help!!

2008-07-22 Thread emir.toktar
Dear R users, I´m trying to optimize simultaneously two binomials inequalities used to acceptance sampling, which are nonlinear solution, so there is no simple direct solution. The 'n' represents the sample size and the 'c' an acceptance number or maximum number of defects (nonconforming) in sampl

[R] Optimize jackknife code

2007-12-31 Thread mw-u2
Hi, I have the following jackknife code which is much slower than my colleagues C code. Yet I like R very much and wonder how R experts would optimize this. I think that the for (i in 1:N_B) part is bad because Rprof() said sum() is called very often but I have no idea how to optimize it. #

Re: [R] optimize() stuck in local plateau ?

2007-10-01 Thread Ravi Varadhan
-Original Message- From: Mike Lawrence [mailto:[EMAIL PROTECTED] Sent: Monday, October 01, 2007 10:27 AM To: Ravi Varadhan Cc: 'Rhelp' Subject: Re: [R] optimize() stuck in local plateau ? I may be misunderstanding, but my example seems to v

Re: [R] optimize() stuck in local plateau ?

2007-10-01 Thread Mike Lawrence
p://www.jhsph.edu/agingandhealth/People/Faculty/ > Varadhan.html > > > > -- > -- > > > > -Original Message- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > project.org]

Re: [R] optimize() stuck in local plateau ?

2007-10-01 Thread Ravi Varadhan
alth/People/Faculty/Varadhan.html -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Mike Lawrence Sent: Monday, October 01, 2007 1:29 AM To: Rhelp Subject: [R] optimize() stuck in local plateau ? Hi all, Consider the

Re: [R] optimize() stuck in local plateau ?

2007-10-01 Thread Patrick Burns
Given a univariate problem where the maximum must be between -1 and 1, I would test with a grid of points, then refine that if necessary. Patrick Burns [EMAIL PROTECTED] +44 (0)20 8525 0696 http://www.burns-stat.com (home of S Poetry and "A Guide for the Unwilling S User") Mike Lawrence wrote: >

Re: [R] optimize() stuck in local plateau ?

2007-09-30 Thread Moshe Olshansky
Hi Mike, You function is discontinuous at -0.8, so you can expect everything :-}! But this is not the only problem. The algorithm for optimize never gets there. In general there exists no universal method to find the global maximum of a function (unless it satisfies certain conditions). You can al

[R] optimize() stuck in local plateau ?

2007-09-30 Thread Mike Lawrence
Hi all, Consider the following function: my.func = function(x){ y=ifelse(x>-.5,0,ifelse(x< -.8,abs(x)/2,abs(x))) print(c(x,y)) #print what was tested and what the result is return(y) } curve(my.func,from=-1,1) When I attempt to find the maximum of this function,