Displaying 20 results from an estimated 11000 matches similar to: "applying max elementwise to two vectors"
2005 Aug 20
2
diagonal matrices
Hello all,
I have matrices V.i of dimension n.i x n.i, where i = 1, ..., J, and the sum of n.i equals N. (and n.i ! = n.j)
goal: create one large matrix V, where V has matrices V.i on diagonal.
I create each matrix V.i in a for loop (1 to J), so each time I'd like to augment V with the
most recently calculated V.i, such that I'll have V after the final iteration of the for loop.
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
2006 Sep 07
5
augPred plot in nlme library
All,
I'm trying to create an augPred plot in the nlme library, similar to the
plot on
p.43 of Pinheiro & Bates (Mixed Effects Models in S and S-Plus) for
their Pixel data.
My data structure is the same as the example but I still get the error
msg below.
> comp.adj.UKV <- groupedData(adj.UKV ~ Time | Patient_no/Lisinopril,
data = comp.adj.UKV.frm, order.groups = F)
>
2009 Jul 24
2
How to find the min and max of two variables in a data frame
I have two variables in a data frame, I want to generate two additional
variables. For every observations (i.e. every row), I want the first new
variable 'min' to carry the minimum of the two existing variables, and I
want the second new variable 'max' to carry the maximum of the two existing
variables. I then want to sort the data frame by min and max, and delete
duplicated rows
2005 Sep 05
3
help
Dear helpeRs,
I seem to be a little bit confused on the result I am getting from the
few codes below:
> u=v=seq(0,1,length=30)
> u
[1] 0.00000000 0.03448276 0.06896552 0.10344828 0.13793103 0.17241379
[7] 0.20689655 0.24137931 0.27586207 0.31034483 0.34482759 0.37931034
[13] 0.41379310 0.44827586 0.48275862 0.51724138 0.55172414 0.58620690
[19] 0.62068966 0.65517241 0.68965517 0.72413793
2006 Sep 12
11
levels of factor when subsetting the factor
All,
When I take a subset of a factor the reduced factor still maintains all
the original levels of the factor when say forming the key in a plot.
The data is correct, but the variable still "remembers" the original
levels. See below for reproducible code. Does anyone know how to fix
this?
cheers,
dave
fact = as.factor(c(rep("A", 3),rep("B", 3), rep("C",
2006 Sep 23
4
plotting grouped data object
All,
I'd like to plot the main relationship of a grouped data
object for all levels of a factor in a single panel.
The sample code below creates a separate panel for each level
of the factor. I realize that this could be done in other ways,
but I'd like to do it via plotting the grouped data object.
thanks!
dave
z = rnorm(18, mean=0, sd=1)
x = rep(1:6, 3)
y =
2000 Mar 20
1
Elementwise c() for lists
I have two lists of equal lengths. Each one consists of vectors. Is
there an elegant way to combine them elementwise? Elegant means: without
loops.
For instance, for
> jja_list(1:3,4:7)
> jjb_list(rep(0,4),(2,5))
I would like to get:
> list(c(1:3,rep(0,4)),c(4:7,rep(2,5))).
--- D.Trenkler ---
************************************************************************
*********
2004 Oct 18
2
concatenating lists elementwise
Hi
How do I concatenate two lists element-by-element?
Example:
list.1 <- list(temperature=c("hot","cold") , size=c("big","medium"))
list.2 <- list(temperature=c("lukewarm") , size=c("massive","tiny"))
list.wanted <- list(temperature=c("hot","cold","lukewarm") ,
2000 Jun 22
1
help
Dear All,
Further to answers to sorting, can someone tell me how can I sort a list
that contains duplicates (name) but keeping the duplicates together when
sorting the values.
e.g., a data frame with name (in duplicates), Mvalues(may be different for
the duplicates)
name M
1234 8
1234 8.3
4321 9
4321 8.1
If I sort by M, it will be 1234, 4321, 1234, 4321 but I want to keep the
duplicates together,
2008 Jan 24
3
Alternating numbers in rep()
All,
I'm trying to obtain a one-liner to generate a certain sequence of
alternatign numbers.
Consider:
> unlist(rep(list(c(1,2), c(3,4)), each = 6))
[1] 1 2 1 2 1 2 1 2 1 2 1 2 3 4 3 4 3 4 3 4 3 4 3 4
I'd like the result to be as above but continue until 38. Of course, I
could hardcode this going up to c(37,38), but is there a more elegant way?
Thanks!
David
2006 Jun 27
2
supplying dynamic main argument to plot?
All,
Simple question but I don't seem to be able to find the answer in the
documentation:
When using "plot" within a loop, is there any way to supply the argument
to "main" dynamically,
i.e., so that the title is Patient k below as the loop cycles through
each value of k?
plot(x,y, xlim=c(0,250), ylim=c(0,1000), xlab="gamma", ylab="r1",
2006 Dec 22
1
Base R: applying min/max functions() to character string vectors (PR#9428)
Full_Name: Xiao Gang FAN
Version: 2.4.0
OS: Windows XP
Submission from: (NULL) (159.50.101.9)
Dear All,
This is not really a bug report, but rather a change wish to the Base R
behaviour
on some functions when applying them to character strings vectors/matrices.
Actually in R, we can do thinks like, the most naturally way in this the world:
> "a" < "b"
[1] TRUE
>
2006 Jun 28
5
sapply question
sent this to the list yesterday but didn't see it listed in the daily
summary ... apologies if you receive it
twice ...
________________________________
From: Afshartous, David
Sent: Tuesday, June 27, 2006 10:02 AM
To: 'r-help@stat.math.ethz.ch'
Subject: sapply question
All:
I'm trying to use sapply to break up data within another function.
(tapply doens't seem to work
2002 Sep 09
1
Monotonic interpolation
Has anyone got a function for smooth monotonic interpolation of a
univariate function? I'm after something like the NAG function PCHIM
which does monotonic Hermite interpolation. Alternatively, montononic
cubic spline interpolation.
Please reply directly.
Rob Hyndman
___________________________________________________
Rob J Hyndman
Associate Professor & Director of Consulting
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
2006 Sep 06
1
Covariance/Correlation matrix for repeated measures data frame
All,
I have a repeated measures data frame and was wondering if the
covariance matrix can be
calculated via some created indexing or built-in R function.
Specifically, say there are 3 variables, where potassium concentration
is measured 6 times on each patient.
Patient number (discrete)
Time (1 to 6, discrete)
Potassium (continuous variable)
I want the covariance/correlation matrix for the
2005 Aug 09
2
numeric operations w/ lists
Hello all,
X is a list of 20 lists, and each individual list has 65 elements.
Y is a list of 65 elements.
WANT: subtract Y from each of the 20 lists in X.
Here's what I tried and the error messages:
> X - rep(Y, 20)
Error in X - rep(Y 20) : non-numeric argument to binary operator
I tried several methods w/o success. Any suggestions kindly
appreciated.
Thanks,
Dave
ps - please copy
2007 Feb 19
6
Data frame: how to create list of row max?
Dear all,
Can anyone please shed some light onto how to do this?
This will give me all "intensity" columsn in my data frame:
intensityindeces <- grep("^Intensity",names(dataframe),value=TRUE)
This will give me the maximum intensity for the first row:
intensityone <- max(dataframe[1,intensityindeces])
What I'm now looking for is how to dfo this for the whole data
2007 Feb 01
3
Help with efficient double sum of max (X_i, Y_i) (X & Y vectors)
Greetings.
For R gurus this may be a no brainer, but I could not find pointers to
efficient computation of this beast in past help files.
Background - I wish to implement a Cramer-von Mises type test statistic
which involves double sums of max(X_i,Y_j) where X and Y are vectors of
differing length.
I am currently using ifelse pointwise in a vector, but have a nagging
suspicion that there is a