Displaying 20 results from an estimated 4000 matches similar to: "plot x-axis DateTime NOT evenly spaced"
2013 Mar 18
4
plotting CIE chromaticity diagram?
Has anyone plotted or is it possible to plot
CIE *xy* chromaticity diagram
http://en.wikipedia.org/wiki/File:CIE1931xy_blank.svg
I need this plot in color.
ishida
[[alternative HTML version deleted]]
2013 Mar 11
3
take two columns from a set of lists
say I have a matrix and lists like
x <- matrix(c(12.1, 3.44, 0.1, 3, 12, 33.1, 1.1, 23), nrow=2)
x.list <- lapply(seq_len(nrow(x)), function(i) x[i,])
if I want a column of the matrix x, I write
x[, 2]
for example.
But how can I do something similar for a set of lists, x.list, above?
> x.list
[[1]]
[1] 12.1 0.1 12.0 1.1
[[2]]
[1] 3.44 3.00 33.10 23.00
unlist(x.list)[,2] does
2013 Mar 10
2
list + lapply insead of matrix + apply
I need to develop a simple list manipulation. Although it seems easier to
do it in matrix form, but I need it in list form.
I have a matrix
x <- matrix(c(12.1, 3.44, 0.1, 3, 12, 33.1, 1.1, 23), nrow=2)
for list form example, the conversion is
x.list <- lapply(seq_len(nrow(x)), function(i) x[i,])
### list version
calcnorm=function(a, b){
diff <- mapply("-", a, b)
2012 Oct 03
1
distinguishing input objects for a function
platform x86_64-apple-darwin9.8.0
arch x86_64
os darwin9.8.0
system x86_64, darwin9.8.0
version.string R version 2.13.1 (2011-07-08)
I am trying to write a function that takes a few objects as input.
test <- function(directory, num = 1:100) {
> }
the argument, "num", has the default value. But when the function is
called, it can take an array
2013 Mar 08
1
reduce the size of list
hi. I have a list like
x <- list(1:10,11:20,21:30)
It's a sort of a 3 x 10 matrix in list form.
I would like to reduce the dimension of this list.
it would be something like
list(1:3, 11:13, 21,23)
I tried
x[,1:3]
does not work of course. Neither
lapply(x, [1:3])
works...
Any suggestions?
ishida
[[alternative HTML version deleted]]
2013 Mar 13
1
image color analysis
I am not sure if I should ask this question in this list. But I'll try.
Currently I am trying to analyze images using EBImage and biOps.
One of the features that I need to extract from various images is the color
spectrum, namely, which colors each image consists of.
So, each image hopefully can be converted into some sort of color histogram
so that color ingredients are easily comparable
2013 May 07
4
create unique ID for each group
Hey All,
I have a dataset(dat1) like this:
ObsNumber ID Weight
1 0001 12
2 0001 13
3 0001 14
4 0002 16
5 0002 17
And another dataset(dat2) like this:
ID Height
0001 3.2
0001 2.6
0001
2008 Mar 25
2
Compare two data sets
I would like to compare two data sets saved as text files (example below) to determine if both sets are identical(or if dat2 is missing information that is included in dat1) and if they are not identical list what information is different between the two sets(ie output "a1", "a3" as the differing information). The overall purpose would be to remove "a1" and
2012 Jun 07
3
conditional statement to replace values in dataframe with NA
Hello and thanks for helping.
#some data
L3 <- LETTERS[1:3]
dat1 <- data.frame(cbind(x=1, y=rep(1:3,2), fac=sample(L3, 6, replace=TRUE)))
#When x==1 and y==1 I want to replace the 1 values with NA
#I can select the rows I want:
dat2<-subset(dat1,x==1 & y==1)
#replace the 1 with NA
dat2$x<-rep(NA,nrow(dat2)
dat2$y<-rep(NA,nrow(dat2)
#select the other rows and rbind
2013 Sep 02
1
R dataframe and looping help
HI,
You may try this:
dat1<- read.table(text="
CustID TripDate Store Bread Butter Milk Eggs
1 2-Jan-12 a 2 0 2 1
1 6-Jan-12 c 0 3 3 0
1 9-Jan-12 a 3 3 0 0
1 31-Mar-13 a 3 0 0 0
2 31-Aug-12 a 0 3 3 0
2 24-Sep-12 a 3 3 0 0
2 25-Sep-12 b 3 0 0 0
",sep="",header=TRUE,stringsAsFactors=FALSE)
dat2<- dat1[,-c(1:3)]
res<- lapply(seq_len(ncol(dat2)),function(i)
2013 Mar 27
9
conditional Dataframe filling
Hi everyone:
This may be trivial but I just have not been able to figure it out.
Imagine the following dataframe:
a b c d
TRUE TRUE TRUE TRUE
FALSE FALSE FALSE TRUE
FALSE TRUE FALSE FALSE
I would like to create a new dataframe, in which TRUE gets 0 but if
false then add 1 to the cell to the left. So the results for the
example above should be something like:
a b c
2010 Mar 22
1
Replacing elements of list
Dear all,
I have following two list object, both are basically collection of matrices
:
dat1 <- matrix(rnorm(25*6), ncol=6)
dat1 <- split(dat1, seq(5,25,by=5))
dat1 <- lapply(dat1, matrix, ncol=6)
dat2 <- matrix(rnorm(25*4), ncol=4)
dat2 <- split(dat2, seq(5,25,by=5))
dat2 <- lapply(dat2, matrix, ncol=4)
Now I want to replace last 4 columns of each matrix at "dat1"
2013 Mar 04
1
installing biOps on MacOSX fails
version.string R version 2.15.2 (2012-10-26)
I am trying to install biOps on MacOS X 10.8.2
First, I have tiff, fftw-3, jpeg
and set paths like
cd /usr/include
sudo ln -s /usr/local/include/fftw3.h
for x in /usr/local/include/j*.h; do sudo ln -s $x; done
for x in /usr/local/include/tiff*.h; do sudo ln -s $x; done
cd /usr/lib
for x in /usr/local/lib/libfftw3.*; do sudo ln -s $x; done
for x in
2013 Apr 29
4
expanding a presence only dataset into presence/absence
Hello,
I'm working with a very large dataset (250,000+ lines in its' current form)
that includes presence only data on various species (which is nested within
different sites and sampling dates). I need to convert this into a dataset
with presence/absence for each species. For example, I would like to expand
"My current data" to "Desired data":
My current data
2013 Apr 12
2
split date and time
Hi R experts,
For example I have a dataset looks like this:
Number TimeStamp Value
1 1/1/2013 0:00 1
2 1/1/2013 0:01 2
3 1/1/2013 0:03 3
How can I split the "TimeStamp" Column into two and return a new table like
this:
Number Date Time Value
1 1/1/2013 0:00 1
2 1/1/2013 0:01 2
3 1/1/2013 0:03 3
Thank!
[[alternative HTML version
2012 Jul 01
2
list to dataframe conversion-testing for identical
HI R help,
I was trying to get identical data frame from a list using two methods.
#Suppose my list is:
listdat1<-list(rnorm(10,20),rep(LETTERS[1:2],5),rep(1:5,2))
#Creating dataframe using cbind
dat1<-data.frame(do.call("cbind",listdat1))
colnames(dat1)<-c("Var1","Var2","Var3")
#Second dataframe conversion
2012 Oct 04
3
R combining vectors into a data frame but without a continuous common variable
Hello,
I have two different files which I'd like to combine to make one data frame
but I've no idea how to do it! The first file has two columns; one is the
date, the following is a binary code for debris flow events. Then my other
file has also two columns; the date and then precipitation data.
The thing is, is that the two date columns don't all contain the same dates.
The binary
2012 Aug 13
4
if else elseif for data frames
Hi all,
It seems like I cannot use normal 'if' for data frames. What would be the
best way to do the following.
if data$col1='high'
data$col2='H'
else if data$col1='Neutral'
data$col2='N'
else if data$col='low'
data$col2='L'
else
#chuch a warning?
Note that col2 was not an existing column and was newly assigned for this
2010 Mar 30
2
Need help to split a given matrix is a "sequential" way
I need to split a given matrix in a sequential order. Let my matrix is :
> dat <- cbind(sample(c(100,200), 10, T), sample(c(50,100, 150, 180), 10,
> T), sample(seq(20, 200, by=20), 10, T)); dat
[,1] [,2] [,3]
[1,] 200 100 80
[2,] 100 180 80
[3,] 200 150 180
[4,] 200 50 140
[5,] 100 150 60
[6,] 100 50 60
[7,] 100 100 100
[8,] 200 150 100
[9,]
2007 Jun 23
2
Names of objects passed as ... to a function?
Dear list,
I have a function whose first argument is '...'. Each element of '...'
is a data frame, and there will be at least 2 data frames in '...'. The
function processes each of the data frames in '...' and returns a list,
whose components are the processed data frames. I would like to name the
components of this returned list with the names of the original data