Displaying 20 results from an estimated 20000 matches similar to: "Procuct of a sequence or vector"
2010 Dec 16
5
test whether all elements of a vector are identical
Dear list,
this might be an easy one, but I could figure out a solution (or how to
google the right term).
Is there any way to test whether all elements of a vector are identical?
For numeric vectors I would use
sum(diff(vector)==0)==0
but I have character vectors. Any Ideas?
Cheers
Jannis
2012 Nov 18
2
list.files, recursively
Dear R developers,
as far as I understand the manual of list.files(), there is only a way
to exclude directories from the returned vector if you use list.files
recursively. In non recursive mode, there seems to be no way of
excluding directories (the include dirs argument does not seem to have
any effect). Would it not be more intuitive and practical to allow the
switching off of directory
2011 Oct 05
3
help with regexp
Dear list memebers,
I am stuck with using regular expressions.
Imagine I have a vector of character strings like:
test <- c('filename_1_def.pdf', 'filename_2_abc.pdf')
How could I use regexpressions to extract only the 'def'/'abc' parts of these strings?
Some try from my side yielded no results:
testresults <-
2012 Jun 15
2
time zones and the chron to POSIXct conversion
Hey R folks,
i found some strange (to me) behaviour with chron to POSIXct conversion.
The two lines of code result in two different results, on ewith the
correct time zone, one without:
library(chron)
as.POSIXct(chron('12/12/2000'), tz = 'UTC')
as.POSIXlt(chron('12/12/2000'), tz = 'UTC')
Only the code below would give me a POSIXct object with the correct time
2013 Apr 08
4
checkUsage from codetools shows errors when function uses functions from loaded packages
Dear list members,
I frequently program small scripts and wrap them into functions to be
able to check them with checkUsage. In case these functions (loaded via
source or copy pasted to the R console) use functions from other
packages, I get this error:
no visible global function definition for ?xxxxxxx?
For example:
test = function() {
require(plotrix)
color.legend()
}
2011 Aug 01
3
General indexing in multidimensional arrays
Dear R community,
I have a general question regarding indexing in multidiemensional arrays.
Imagine I have a three dimensional array and I only want to extract on
vector along a single dimension from it:
data <- array(rnorm(64),dim=c(4,4,4))
result <- data[1,1,]
If I want to extract more than one of these vectors, it would now really
help me to supply a logical matrix of the
2012 Feb 27
2
problem with assign and get
Dear list members,
does anyone have an idea why the following construction does not work
but gives the following error message:
assign('test', array(1:10, dim=c(10,10)))
dimnames(get('test')) <- list(1:10,1:10)
Error in dimnames(get("test")) <- list(1:10, 1:10) :
target of assignment expands to non-language object
What could be a way to get this to work?
2011 May 04
1
Problems saving ff objects
Dear list,
I am trying to understand and use the ff package. As I had some problems saving some ff objects, and as I did not fully manage to understand the whole concept of *.ff, *.ffData and *.RData with the help of the documentation, I tried to reproduce the examples from the help of ffsave.
When I ran, however : (copied from the help)
message("let's create some ff objects")
2010 May 18
4
scaling with relative units in plots or retrieving axes limits in plots
Dears,
a way to define x and y positions in plots in relative numbers (e.g in fractions between 0 and 1 referring to relative positions inside the plot region) would really help me. One example I would need this to would be to add text via text() to a plot always at a defined spot, e.g the upper left corner. Until now I always determined maximum x and y values and used those, but defining
2011 Jan 12
2
RNetCDF: retrieving variable names and units
Dear List,
does anybody has experience with the RNetCDF package? I manage to open a connection and copy data from a ncdf file but would need a way to automatically retrieve variable names (ideally all of them from one file) and units from the file.
Any ideas?
Jannis
2011 Apr 27
3
setting options only inside functions
Dear list members,
is it possible to set some options only inside a function so that the original options are restored once the function is finished or aborted due to an error? Until now I do something like:
dummy=function()
{
old.options=options(error=dummy1())
....
options(old.options)
}
This works for most cases but when the function terminates because of an error and its last
2013 Jun 20
2
showing error line
Dear R users,
i am trying to get the line number of the code where an error is
produced. With the options:
options(keep.source = TRUE, show.error.locations = TRUE,
keep.source.pkgs = TRUE)
I have managed to get the error locations to show up when i source the
respective files. They do not, however, show up for the same errors when
I use installed packages. Do I have to build these packages
2011 Aug 03
2
syntax with do.call and `[`
Dear List,
i would like to mimic the behaviour or the following indexing with a do.call construct to be able to supply the arguments to `[` as a list:
test = matrix[1:4,2]
result = test[2,]
My try, however, did not work:
result = do.call(`[`,list(test,2,NULL))
result = do.call(`[`,list(test,2,))
result = do.call(`[`,list(test,2,''))
How can I use the do.call in that way with
2009 Dec 01
1
Error message when logical indexing vecor is all FALSE
Dears,
is there any way to "switch off" or work around the error message that
pops up when I do something like:
A<-B['logical vector']
and when 'logical vector' only consists of FALSE values? My problem is
that this message always kicks me out of my loops and always testing via
an if clause whether 'logical vector' contains any TRUE values is much
too
2010 Mar 09
1
find out commands in package
Dears,
I am trying to implement some R package which is still under construction and has not yet been submitted to CRAN (RSSA, http://anton.korobeynikov.info/software). Documentation is yet very poor (or i just did not find it), so I am wondering whether there is any way to retrieve a list of commands available in this package from within R? And to find out whether the package is successfully
2011 Nov 24
1
content of global environment with dump.frames()
Dear R users,
I am using dump.frames() to investigate the content of the different environments in cases of errors or during certain steps of a non interactive calculation. I am, however, wondering about how to see the content of the global environment at the moment that dump.fames() was invoked. Her is some test piece (careful about the rm(list=ls(), remove the # if you know what you are doing
2011 Sep 28
3
dump.frames, debugger and the "..." argument
Dear List,
i run R non interactively and use option(error = dump.frames) to reconstruct the cause of errors for debugging. One of the functions in the call stack however uses the "..." (dot dot dot) argument. When I run debugger() and try to browse to this functions' environment I get the following error message:
Error in get(.obj, envir = dump[[.selection]]) :
argument
2009 Dec 01
1
assigning values to parameters, based on different names
Dear R help community,
I have tumbleled across some problem quite often and could not find a
solution for it (or was not able to google the right terms).
I am wondering whether there is a way to tell R to assign a value of
parameter X to parameter B while the actual name of parameter X is given
by parameter C. Like this:
C<-"name of parameter X"
B<- parameter X which has the
2014 Apr 29
1
access environment in which an error occurred
Dear R developers,
i have already send the question below to r-help but got no responses.
Perhaps it is more suitable for r-devel due to its rather technical
level. It would really help me to find a solution (or to find out that
there is none).
Is there any way to access/print/save the content of an environment in
which an error occoured?
Imagine the following testcase:
test =
2011 Dec 05
1
installing several versions of R (2.14 and 2.12.2) on the same system on Ubuntu
Dear R users,
besides the current R 2.14 I would like to install a second version of R (2.12.2) on my Ubuntu system. The current version is easily installed as a precompiled package from Cran but I am heavily fighting with the older version. I tried to follow the instructions here:
http://cran.r-project.org/doc/manuals/R-admin.html
Unfortunately I got totally confused by all the different