Displaying 20 results from an estimated 1000 matches similar to: "Does R accumulate memory"
2005 Jan 18
4
Data Simulation in R
Dear List:
A few weeks ago I posted some questions regarding data simulation and
received some very helpful comments, thank you. I have modified my code
accordingly and have made some progress.
However, I now am facing a new challenge along similar lines. I am
attempting to simulate 250 datasets and then run the data through a
linear model. I use rm() and gc() as I move along to clean up the
2005 Jan 20
1
Windows Front end-crash error
Dear List:
First, many thanks to those who offered assistance while I constructed
code for the simulation. I think I now have code that resolves most of
the issues I encountered with memory.
While the code works perfectly for smallish datasets with small sample
sizes, it arouses a windows-based error with samples of 5,000 and 250
datasets. The error is a dialogue box with the following:
"R
2008 Feb 15
1
Questions about EM algorithm
Dear all:
Assume I have 3 distributions, x1, x2, and x3.
x1 ~ normal(mu1, sd1)
x2 ~ normal(mu2, sd2)
x3 ~ normal(mu3, sd3)
y1 = x1 + x2
y2 = x1 + x3
Now that the data I can observed is only y1 and y2. It is
easy to estimate (mu1+m2), (mu1+mu3), (sd1^2+sd2^2) and
(sd1^2+sd3^2) by EM algorithm since
y1 ~ normal(mu1+mu2, sqrt(sd1^2+sd2^2)) and
y2 ~ normal(mu1+mu3, sqrt(sd1^2+sd3^2))
However, I want
2014 Feb 27
1
Join Samba4 member server to Windows AD
Hello everybody,
I need to setup a Domain/subdomain environment with Windows AD. All the
DCs run Windows Server 2012 R2. All domains (root and subdomains) The
forest and domain functional level are set to Windows 2008 R2.
I want to use Samba 4 server as fileservers in these domains, but up to
now I have trouble adding Samba 4 member servers to Windows AD.
My test environment is made of 2
2013 Feb 01
2
How does this function print, why is n1 which equals 1 printed as 2?
Windows 7, R 2.12.1
Colleagues,
I am trying to understand the n.for.2means function. The code below is a copy of the function (renamed to n.for.2means.js). I have inserted a single line of code towards the bottom of the function which uses the cat function to print the value of n1. You will note the value (preceded by stars) is printed as 1.
The function (1) prints a lot of output without any
2011 Jan 10
2
Calculating Portfolio Standard deviation
Dear R helpers
I have following data
stocks <- c("ABC", "DEF", "GHI", "JKL")
prices_df <- data.frame(ABC = c(17,24,15,22,16,22,17,22,15,19),
DEF = c(22,28,20,20,28,26,29,18,24,21),
GHI = c(32,27,32,36,37,37,34,23,25,32),
2006 Nov 24
1
barplot help needed
hello,
I would like to create the following barplot:
I have 4 different data sets (same length + stddev for each data point)
data1
sd1
data2
sd2
data3
sd3
data4
sd4
now, I'd like to plot in the following way:
data1[1],data2[1],data3[1],data4[1] with it's sd-values side-by-side at
one x-axis label (named "position 1") and each bar in different colors.
2004 Sep 16
3
Estimating parameters for a bimodal distribution
For several years, I have been using Splus to analyze an ongoing series of
datasets that have a bimodal distribution. I have used the following
functions, in particular the ms() function, to estimate the parameters: two
means, two standard deviations, and one proportion. Here is the code I've
been using in S:
btmp.bi <- function(vec, p, m1, m2, sd1, sd2)
{
2010 Nov 23
1
Barplot and plot means with confidence intervals in the same plot
I want to obtain a barplot with error bars and a mean plot with error bars
with other scale on the left in the same plot. I need help to get the same
x axis (centered) when overlay two plots (barplot2 and plotCI (or
lineplot.CI) with errorbars), with diferent y axis. I use par (new=T) but
the X axis names are not centered with the figures.
An example of my data:
2013 Jan 13
1
How to combine two loops?
Hello R-helpers,
I want to ask your opinion since I am not so sure how to do it. This is regarding one part of my paper project and my situation is:
Stage I
I have 2 groups and for each group I need to compute the following steps;
i) Generate 3 random numbers from normal distribution and square them.
ii) Repeat step 1 for 15 times and at the end I will get 15 random numbers.
I already done
2012 Jun 04
1
simulation of modified bartlett's test
Hi, I run this code to get the power of the test for modified bartlett's
test..but I'm not really sure that my coding is right..
#normal distribution unequal variance
asim<-5000
pv<-rep(NA,asim)
for(i in 1:asim)
{print(i)
set.seed(i)
n1<-20
n2<-20
n3<-20
mu<-0
sd1<-sqrt(25)
sd2<-sqrt(50)
sd3<-sqrt(100)
g1<-rnorm(n1,mu,sd1)
g2<-rnorm(n2,mu,sd2)
2010 Jul 18
2
loop troubles
Hi all, I appreciate the help this list has given me before. I have a
question which has been perplexing me. I have been working on doing a
Bayesian calculating inserting studies sequentially after using a
non-informative prior to get a meta-analysis type result. I created a
function using three iterations of this, my code is below. I insert prior
mean and precision (I add precision manually
2002 Mar 01
3
Power of t-test in R vs. S-PLUS
Dear all,
I found a discrepancy while performing a power calculation for a two sample
t-test in R and S-PLUS, respectively.
For given values of sample number (5 each), sd (0.2) , significance level
(0.01), and a desired power (80%) I looked for the difference in means.
These values differ: 0.5488882 in R and 0.4322771 in S-PLUS (see dump
below).
Did I overlook any detail or confuse some
2006 Jul 25
1
Multiple tests on repeated measurements
Dear R-helpers:
My question is how do I efficient and valid correct for multiple tests in a repeated measurement design:
Suppose we measure at two distinct visits with repeated subjects a treatment difference on the same variable.
The treatment differences are assessed with a mixed model and adjusted by two methods for multiple tests:
# 1. Method: Adjustment with library(multcomp)
2011 Nov 11
1
Fwd: Use of R for VECM
----- Forwarded Message -----
From: vramaiah at neo.tamu.edu
To: "bernhard pfaff" <bernhard.pfaff at pfaffikus.de>
Sent: Friday, November 11, 2011 9:03:11 AM GMT -06:00 US/Canada Central
Subject: Use of R for VECM
Hello Fellow R'ers
I am a new user of R and I am applying it for solving Bi-Variate (Consumption and Output) VECM with Co-Integration (I(1)) with three lags on
2009 Jan 27
1
Problem with RMA using limma, oligo and pdInfoBuilder packages
Hi,
I am a Ph.D. student from Québec, Canada. I’m a beginner with R and
Bioconductor. Until now the only experience I have is in analyzing
microarray data using affy and limma packages. Now I am trying to analyze
Rat Gene 10 st arrays and I would like to run RMA analysis and Smyth
moderated t test on those arrays. Since no cdf official package is available
for those arrays, after reading many
2007 Nov 17
11
slog tests on read throughput exhaustion (NFS)
I have historically noticed that in ZFS, when ever there is a heavy
writer to a pool via NFS, the reads can held back (basically paused).
An example is a RAID10 pool of 6 disks, whereby a directory of files
including some large 100+MB in size being written can cause other
clients over NFS to pause for seconds (5-30 or so). This on B70 bits.
I''ve gotten used to this behavior over NFS, but
2008 Feb 28
1
calculate sd for each row on some columns of a dataframe
Hi,
I've got a dataframe like this:
df = data.frame(a=rnorm(100,1),b=rnorm(100,10),c=rnorm(100,100),d=rnorm(100,-100))
and I want to calculate sd1 for (a,b,c) for each entry, and sd2 for
(b,c,d) for each entry.
I don't seem to find the answer using aggregate or apply,
How can I do this?
Thanks in advance,
Cheers,
Albert.
2011 Nov 29
1
Create an identifier variable
I am needing to create a new identifier variable for a data set which has no
ID variable in the original file. I am basically wanting to take the count
of each row and add "sd" in front of it - so it would look like so
sd1
sd2
sd3
sd4
sd5 etc.......
I have no idea how to do this. I am a SAS user trying to learn R. This
question may have been answered previously, but I could be
2011 Sep 15
1
How to compute the power of a wilcoxon test?
Hello All,
I posted a similar question before, but the direction was driven to whether
my case is suitable for a wilcoxon test. After research about the
appropriateness, I am pretty sure that a wilcoxon test is the right tool for
my case. But how to compute the power of the test is still an unanswered
question bothering me.
The basic stats of my two paired samples are:
mean1 = 0.0032, sd1 =