Displaying 20 results from an estimated 3000 matches similar to: "using "rollapply" to calculate a moving sum or running sum?"
2009 Mar 23
1
performance: zoo's rollapply() vs inline
zoo's rollapply() function appears to be extremely useful for plugging in a
function on-the-fly to run over a window. With inline, there is a lot more
coding and room for error, and the code is less portable because the user
has to have R compiling set up or it won't work.
However, rollapply() seems to be really slow. Several orders of magnitude
slower than inline, in fact. I don't
2010 Jan 13
1
Rollapply
Hi
I would like to understand how to extend the function (FUN) I am using in
rollapply below.
######################################
With the following simplified data, test1 yields parameters for a rolling
regression
data = data.frame(Xvar=c(70.67,70.54,69.87,69.51,70.69,72.66,72.65,73.36),
Yvar =c(78.01,77.07,77.35,76.72,77.49,78.70,77.78,79.58))
data.z = zoo(d)
test1 =
2008 Jul 31
1
rollapply() to portions of a matrix
Hi everyone,
I have a rollapply statement that applies a function, in steps, over a data
matrix as follows:
#Code start
testm<-rollapply(mat, 100, by=100, min, na.rm=F)
#Code end
This moves down matrix 'mat' and calculates the minimum value over a 100 row
range, every 100 rows (i.e. no overlaps). NAs are not removed.
I want to modify this statement somehow so that the rollapply()
2011 Aug 12
2
rollapply.zoo() with na.rm=TRUE
Hi.
I'm comparing output from rollapply.zoo, as produced by two versions
of R and package zoo. I'm illustrating with an example from a R-help
posting 'Zoo - bug ???' dated 2010-07-13.
My question is not about the first version, or the questions raised in
that posting, because the behaviour is as documented. I'm puzzled as
to why na.rm no longer is passed to mean, i.e. why
2010 Apr 09
3
"fill in" values between rollapply
Hi,
Sorry ahead of time for not including data with this question.
Using rollapply to calculate mean values for 5 day blocks, I'd use this:
Roll5mean <- rollapply(data, 5, mean, by=5, align = c("left"))
My question is, can someone tell me how to fill in the days between each of
these means with the previously calculated mean? If this doesn't make
sense, I will clarify and
2011 Apr 03
1
zoo:rollapply by multiple grouping factors
# Hi there,
# I am trying to apply a function over a moving-window for a large
number of multivariate time-series that are grouped in a nested set of
factors. I have spent a few days searching for solutions with no luck,
so any suggestions are much appreciated.
# The data I have are for the abundance dynamics of multiple species
observed in multiple fixed plots at multiple sites. (I total I
2012 Oct 26
1
rollapply() by time, not entries (width)
Hi all-
Thank you for reading my post. Please bear in mind that I'm very much a
newbie with R! My question is this:
I'm trying to use rollapply() on an irregular time series so I can't simply
use the width parameter (I don't think). Rather than last 5 entries, I'd
like to rollapply on last 6 months (for example). What would be the proper
course of action for this?
Thanks!
2009 Jun 19
1
function rollapply
Hi,
I faced with problem when start using function - rollapply(returns, 3 ,
mean)
Error in UseMethod("rollapply") :
No suitable Method for "rollaply"
How can I fix the problem? Thank you for help.
--
Best regards,
Andy Fetsun
[[alternative HTML version deleted]]
2012 Jan 24
1
problems with rollapply {zoo}
Here is a relatively simple script (with comments as to the logic
interspersed):
# Some of these libraries are probably not needed here, but leaving them in
place harms nothing:
library(tseries)
library(xts)
library(quantmod)
library(fGarch)
library(fTrading)
library(ggplot2)
# Set the working directory, where the data file is located, and read the
raw data
2009 Jul 07
1
Error in Rolling window of function - rollapply
Dear Colleagues,
I have faced with the problem that function rollaply with rolling window for
calculation of volatility doesn't give the all results of calculations.
I have run the rolling window for calculation in Excel and obtained that the
number of outputs for Excel is 36 and for R is 18. The total number of
observations is 37. In the attachment you can find pdf of the Excel and
Excel
2007 Nov 30
1
rollapply on zoo object
Dear R users.
I have zoo object "size_june" containing market-capital values:
> dim(size_june) # market-cap data of 625 firms for 20 years
[1] 20 625
> class(size_june)
[1] "zoo"
> size_june # colnames = "size.firmcode"
size.34020 size.4710 size.11050 size.10660 size.9540 size.8060
size.16160 size.8080 size.9280
1988-06-30 NA
2012 Jul 10
1
Help with vectors and rollapply
Hello
I have a vector a =(-2,0,0,0,1,0,0,3,0,0,-4)
I want to replace all zeros into previous non-zero state. So for instance the above vector should be converted into:
a= (-2,-2,-2,-2,1,1,1,3,3,3,-4)
I tried many things and finally concluded that probably(?) rollapply may be the best way?
I tried
f= function(x){
ifelse(x==0,Lag(x),x)
}
And then, rollappy(a,1,f) and that
2012 Oct 16
2
sliding window analysis with rollapply
Dear List members
I want to do the sliding window analysis of some specific values. Here is my code:
require(zoo)
dat <- read.table("chr1.txt", header = TRUE, sep="\t")
dat2 <- cbind(dat[1,3]) #The first column is also important. It represents the position of the site on the chromosome.
TS <- zoo(c(dat2))
a <- rollapply(TS, width=1000000, by=200000, FUN=mean,
2009 Jul 20
1
S4 method dispatch with inheritance
Hi,
I'm trying to create a new S4 class (myMatrix) which for now just
extends dgCMatrix (from package Matrix). Then I want to use "[" which is
defined in Matrix.
Out of the box with "[" (defined in Matrix) I lose the class information
and the result is an object of class dgCMatrix. If I specify a
"["-method for myMatrix, it is not used because a signature
2012 Aug 01
1
Error message: $ operator is invalid for atomic vectors
HI,
The code was working perfectly fine yesterday and today, until half an hour ago.? Couldn't find any problems in the code. Still, I am getting error message.
myMatrix <- data.matrix(read.table(text="
Name??????????? Age
ANTONY??????? 27
IMRAN????????? 30
RAJ????????????????? 22
NAHAS????????? 32
GEO??????????????? 42
", header=TRUE))
MinMaxArray? <- data.frame(MIN =
2005 Aug 08
2
computationally singular
Hi,
I have a dataset which has around 138 variables and 30,000 cases. I am
trying to calculate a mahalanobis distance matrix for them and my
procedure is like this:
Suppose my data is stored in mymatrix
> S<-cov(mymatrix) # this is fine
> D<-sapply(1:nrow(mymatrix), function(i) mahalanobis(mymatrix, mymatrix[i,], S))
Error in solve.default(cov, ...) : system is computationally
2011 Aug 17
2
Lattice: problem with setting space between plot and legend
Dear R Users,
I am writing code to present my output data (I'm using Lattice Package).
However, it's essential for me to control space between barchart and legend.
I've read the package's specification, but unfortunately I haven't spot the
information how to do this. Here's the code I've written:
barchart(mymatrix[,1:ncol(mymatrix)],horizontal=FALSE,
2011 Oct 11
2
binding all elements of list (character vectors) to a matrix as rows
dear r-users,
i have got a problem which i am trying to solve:
i have got the following commands:
Mymatrix <- matrix(1:9,ncol=3)
Z <-
list("V1"=c("a","",""),"V2"=c("b","",""),"V3"=c("c","",""),"V4"=c("d","",""))
Mymatrix <-
2005 Jan 21
6
Avoiding a Loop?
Dear R-Helpers,
I have a matrix where the first column is known. The second column is
the result of multiplying this first column with a constant "const". The
third column is the result of multiplying the second column with
"const".....
So far, I did it like this (as a simplified example):
nr.of.columns <- 4
myconstant <- 27.5
mymatrix <- matrix(numeric(0), nrow=5,
2012 Jul 19
2
Line chart with a double matrix
Hello,
I have a double matrix that I want to represent in a line chart. Although I
have seen some examples I still don't manage to get it. My data is this (a
double matrix called mymatrix) :
Blogs Wikis Redes Etiq. SPC LMS
Menor de 30 57.14 28.57 14.29 28.57 57.14 28.57
de 31 a 40 63.83 61.70 29.79 17.02 59.57 70.21
de 41 a 50 72.64 70.75 47.17 20.75 55.66 75.47
Mayor de