Displaying 20 results from an estimated 10000 matches similar to: "aggregate() function, strange behavior for augmented data"
2008 Jun 26
3
Connecting lines across missing data points, xyplot
All,
I have data across 5 time points that I am graphing via xyplot, along with
error bars. For one of the variables I have missing data for two of the
time points. The code below is okay but I can't seem to get the lines to
connect across the missing time points. Does anyone now how to rectify
this?
Cheers,
David Afshartous
library(lattice)
## the data
junk = data.frame(
Visit =
2009 Jan 28
1
Please Help for Augmented Prediction Plot
Hi R users,I have a question about augmented prediction plot (?augPred). The covariate of my data set is c(0, 0.01, 0.1, 1, 10, 100, 1000) and I have fitted a nonlinear mixed effects model.I use plot(augPred(out.nlme....)) to get the augmented prediction plot. However, because the scale of the covariate is too large thus I am not able to see the detail difference at c(0,0.01, 0.1, and 1). Could
2008 Jul 08
1
aggregate() function and na.rm = TRUE
All,
I've been using aggregate() to compute means and standard deviations at
time/treatment combinations for a longitudinal dataset, using na.rm = TRUE
for missing data.
This was working fine before, but now when I re-run some old code it isn't.
I've backtracked my steps and can't seem to find out why it was working
before but not now. In any event, below is a reproducible
2010 Aug 10
4
Function to Define a Function
I am trying to define a general R function that has a function as the output that depends on the user's input arguments (this may make more sense by looking at the toy example below). My real use for this type of code is to allow a user to choose from many parameterizations of the same general model.
My "issue" is that when I compile a package with this type of code in it I get a
2011 Aug 02
2
Help with aggregate syntax for a multi-column function please.
Dear R-experts:
I am using a function called AUC whose arguments are data, time, id, and
dv.
data is the name of the dataframe,
time is the independent variable column name,
id is the subject id and
dv is the dependent variable.
The function computes area under the curve by trapezoidal rule, for each
subject id.
I would like to embed this in aggregate to further subset by each
2017 Jun 01
5
Reversing one dimension of an array, in a generalized case
Hi All:
I have been looking for an elegant way to do the following, but haven't found it, I have never had a good understanding of any of the "apply" functions.
A simplified idea is I have an array, say:
junk(5, 10, 3)
where (5, 10, 3) give the dimension sizes, and I want to reverse the second dimension, so I could do:
junk1 <- junk[, rev(seq_len(10), ]
but what I am
2008 Feb 05
1
Extracting level-1 variance from lmer()
All,
How does one extract the level-1 variance from a model fit via lmer()?
In the code below the level-2 variance component may be obtained via
subscripting, but what about the level-1 variance, viz., the 3.215072 term?
(actually this term squared) Didn't see anything in the archives on this.
Cheers,
David
> fm <- lmer( dv ~ time.num*drug + (1 | Patient.new), data=dat.new )
2010 Jan 21
1
Retrieving an evaluated gradient value (UNCLASSIFIED)
Classification: UNCLASSIFIED
Caveats: NONE
Dear R users,
How can I retrieve an evaluated gradient value from "deriv" function
provided below? I want to retrieve b0 value. Appreciate your help.
Kyong
junk1<-deriv(~(1/b1)*k-b0/b1,"b0",c("k","b0","b1"),formal=T)
junk1(k=0,b0=-14.0236,b1=2.44031)
[1] 5.746647
attr(, "gradient"):
2017 Jun 01
0
Reversing one dimension of an array, in a generalized case
Thanks to all for responses/. There was a question of exactly what was wanted. It is the generalization of the obvious example I gave,
>>> junk1 <- junk[, rev(seq_len(10), ]
so that
junk[1,1,1 ] = junk1[1,10,1]
junk[1,2,1] = junk1[1,9,1]
etc.
The genesis of this is the program is downloading data from a variety of sources on (time, altitude, lat, lon) coordinates, but all
2017 Jun 01
0
Reversing one dimension of an array, in a generalized case
How about this:
f <- function(a,wh){ ## a is the array; wh is the index to be reversed
l<- lapply(dim(a),seq_len)
l[[wh]]<- rev(l[[wh]])
do.call(`[`,c(list(a),l))
}
## test
z <- array(1:120,dim=2:5)
## I omit the printouts
f(z,2)
f(z,3)
Cheers,
Bert
Bert Gunter
"The trouble with having an open mind is that people keep coming along
and sticking things into
2017 Jun 01
0
Reversing one dimension of an array, in a generalized case
On the off chance that anyone is still interested, here is the corrected function using aperm():
z <- array(1:120,dim=2:5)
f2 <- function(a, wh) {
idx <- seq_len(length(dim(a)))
dims <- setdiff(idx, wh)
idx <- append(idx[-1], idx[1], wh-1)
aperm(apply(a, dims, rev), idx)
}
all.equal(f(z, 1), f2(z, 1))
# [1] TRUE
all.equal(f(z, 2), f2(z, 2))
# [1] TRUE
2017 Jun 01
3
Reversing one dimension of an array, in a generalized case
> On 1 Jun 2017, at 22:42, Roy Mendelssohn - NOAA Federal <roy.mendelssohn at noaa.gov> wrote:
>
> Thanks to all for responses/. There was a question of exactly what was wanted. It is the generalization of the obvious example I gave,
>
>>>> junk1 <- junk[, rev(seq_len(10), ]
>
>
> so that
>
> junk[1,1,1 ] = junk1[1,10,1]
> junk[1,2,1] =
2017 Jun 01
1
Reversing one dimension of an array, in a generalized case
Thanks again. I am going to try the different versions. But I probably won't be able to get to it till next week.
This is probably at the point where anything further should be sent to me privately.
-Roy
> On Jun 1, 2017, at 1:56 PM, David L Carlson <dcarlson at tamu.edu> wrote:
>
> On the off chance that anyone is still interested, here is the corrected function using
2017 Jun 01
2
Reversing one dimension of an array, in a generalized case
My error. Clearly I did not do enough testing.
z <- array(1:24,dim=2:4)
> all.equal(f(z,1),f2(z,1))
[1] TRUE
> all.equal(f(z,2),f2(z,2))
[1] TRUE
> all.equal(f(z,3),f2(z,3))
[1] "Attributes: < Component ?dim?: Mean relative difference: 0.4444444 >"
[2] "Mean relative difference: 0.6109091"
# Your earlier example
> z <- array(1:120, dim=2:5)
>
2017 Jun 01
3
Reversing one dimension of an array, in a generalized case
Here is an alternative approach using apply(). Note that with apply() you are reversing rows or columns not indices of rows or columns so apply(junk, 2, rev) reverses the values in each column not the column indices. We actually need to use rev() on everything but the index we are interested in reversing:
f2 <- function(a, wh) {
dims <- seq_len(length(dim(a)))
dims <-
2017 Jun 01
0
Reversing one dimension of an array, in a generalized case
??
> z <- array(1:24,dim=2:4)
> all.equal(f(z,3),f2(z,3))
[1] "Attributes: < Component ?dim?: Mean relative difference: 0.4444444 >"
[2] "Mean relative difference: 0.6109091"
In fact,
> dim(f(z,3))
[1] 2 3 4
> dim(f2(z,3))
[1] 3 4 2
Have I made some sort of stupid error here? Or have I misunderstood
what was wanted?
Cheers,
Bert
Bert Gunter
2009 Jul 24
1
Aggregate, max and time of max
All,
For data consisting of serial measurements on subjects, one may use the
aggregate function to say compute the peak response for each subject for
each design condition. Is there a way to alter this or another one-liner to
also retain the time at which the peak occurred and thus avoid writing a
doing this via a loop? I suppose one could attempt to employ the split
function but that's
2013 Sep 06
1
Dovecot 2.1.7 not starting properly, mail not delivered
On my debian box dovecot does not start properly any more, and mails don't
get delivered or sent. I've googled around without finding any useful leads.
Hopefully someone is willing to educate me. My guess is it must be a config
problem after an upgrade, since I didn't change anything myself directly.
Not sure when it started, since I this mail server is not our default
machine (yet).
2007 Jul 05
3
summarizing dataframe at variable/factor levels
All,
Is there an efficient way to apply say "mean" or "median" to a dataframe
according to say all combinations of two variables in the dataframe?
Below is a simple example and the outline of a "manual" solution that
will work but is not very efficient
(could also generalize this to a function). Searched the archives and
docs but didn't see anything close to
2010 Oct 29
3
Dickey Fuller Test
Dear Users, please help with the following DF test:
=====
library(tseries)
library(timeSeries)
Y=c(3519,3803,4332,4251,4661,4811,4448,4451,4343,4067,4001,3934,3652,3768
,4082,4101,4628,4898,4476,4728,4458,4004,4095,4056,3641,3966,4417,4367
,4821,5190,4638,4904,4528,4383,4339,4327,3856,4072,4563,4561,4984,5316
,4843,5383,4889,4681,4466,4463,4217,4322,4779,4988,5383,5591,5322,5404