Displaying 9 results from an estimated 9 matches for "poplarski".
2011 May 17
4
subsetting a list of dataframes
Hello All,
I have a list of dataframes, and I need to subset it by keeping only those
dataframes in the list that meet a certain criterion. Specifically, I need
to generate a second list which only includes those dataframes whose number
of rows is > 1.
Could someone suggest how to do this? I have come close to what I need with
loops and such, but there must be a less clumsy way...
Many
2011 Jun 05
2
kronecker sum
Dear All,
Could someone please suggest how to find the Kronecker sum of two 2x2
matrices,
i.e. given two matrices:
-A A
a -a
and
-B B
b -b
I need:
-A-B A B 0
a -a-B 0 B
b 0 -A-b A
0 b a -a-b
Many thanks,
Lara
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2010 Nov 15
2
rotate column names in large matrix
Dear List,
I have a large (1600*1600) matrix generated with symnum, that I am using to
eyeball the structure of a dataset.
I have abbreviated the column names with the abbr.colnames option. One way
to get an even more compact view of the matrix would be to display the
column names rotated by 90 degrees.
Any pointers on how to do this would be most useful. Any other tips for
displaying the
2012 Feb 28
2
from data.frame to Venn diagram
Hello All,
I have a data.frame with this structure:
m <- matrix(sample(c(rep('yes', 10, replace = TRUE), rep('no', 10,
replace = TRUE), NA), 500, replace = TRUE), nrow = 100, ncol = 5)
colnames(m) <- colnames(m, do.NULL = FALSE, prefix = "col")
m <- as.data.frame(m)
I need to generate a Venn diagram from this data.frame, displaying the
various intersections of
2010 Nov 19
1
negative axis values in image() and scalebar in cor.plot() {psych}
Dear List,
I sent a related message yesterday, but did not receive it through the
mailing list; on the R-help archives it reads as "An embedded and
charset-unspecified text was scrubbed...". So here it is again, with the
(little) progress I have made since then. Any help would be greatly
appreciated!
I am working with a relatively large correlation matrix (~1600*1600), which
I am
2010 Nov 24
1
diverting output from nested loops
Dear List,
I have a series of nested loops with the structure shown below, and I am
struggling to figure out how to divert output to folders created with
dir.create() within the loops.
What I need is for the output to end up as topNameK/subNameL/objNameM.pdf;
what I get instead is a series of directories topNameK/, directories
subNameL/, and files objNameM.pdf, all in the working directory. Any
2011 Aug 23
1
subsetting a list of matrices
Hi all,
I have an object that looks (roughly) like the following:
l <- list(a = matrix(rnorm(9), 3), b = matrix(rnorm(9), 3), c =
matrix(rnorm(9), 3))
l$a[3,] <- sample(c("Message 1", "Message 2", "Message 3"))
l$b[3,] <- sample(c("Message 1", "Message 2", "Message 3"))
l$c[3,] <- sample(c("Message 1",
2011 Oct 03
1
function recode within sapply
Dear List,
I am using function recode, from package car, within sapply, as follows:
L3 <- LETTERS[1:3]
(d <- data.frame(cbind(x = 1, y = 1:10), fac1 = sample(L3, 10,
replace=TRUE), fac2 = sample(L3, 10, replace=TRUE), fac3 = sample(L3,
10, replace=TRUE)))
str(d)
d[, c("fac1", "fac2")] <- sapply(d[, c("fac1", "fac2")], recode,
"c('A',
2010 Nov 11
1
exploratory analysis of large categorical datasets
Dear List,
I am looking to perform exploratory analyses of two (relatively) large
datasets of categorical data. The first one is a binary 80x100 matrix, in
the form:
matrix(sample(c(0,1),25,replace=TRUE), nrow = 5, ncol=5, dimnames = list(c(
"group1", "group2","group3", "group4","group5"), c("V.1", "V.2", "V.3",