Displaying 20 results from an estimated 3000 matches similar to: "interpreting profiling output"
2007 Mar 31
1
Probem with argument "append" in "Rprof"
Hello,
Appending information to the profiler's output seems to generate
problems. Here is a small example of code :
<code r>
require(boot)
Rprof( memory.profiling = TRUE)
Rprof(NULL)
for(i in 1:2){
Rprof( memory.profiling = TRUE, append = TRUE)
example(boot)
Rprof(NULL)
}
</code>
The problem is that the file Rprof.out contains more than once the
header information:
$ grep
2007 Aug 23
2
read big text file into R
Dear Rs:
Hi, I am trying to read a big text file (nrows=243440, ncols=144). It
seems the computational time of all the read methods
(scan,readtable,read.delim) is not linear to the number of rows I
want to read in: things became really slow once I tried to read in
100000 lines compare to 10000 lines).
If I am reading the profiling result right, I guess scan wouldn't
help either.
My
2009 Nov 10
1
standardGeneric seems slow; any way to get around it?
Hi,
I'm running some routines with standard matrix operations like solve() and
diag().
When I do a profile, the lead item under total time is standardGeneric().
Furthermore, solve() and diag() have much greater total time than self time.
???
I assume there is some time-consuming decision going on in the usual
functions;
is there any way to avoid that and go straight to the calculaions?
Thanks
2009 Mar 03
1
profiler and loops
Hello,
(This is follow up from this thread:
http://www.nabble.com/execution-time-of-.packages-td22304833.html but
with a different focus)
I am often confused by the result of the profiler, when a loop is
involved. Consider these two scripts:
script1:
Rprof( )
x <- numeric( )
for( i in 1:10000){
x <- c( x, rnorm(10) )
}
Rprof( NULL )
print( summaryRprof( ) )
script2:
2013 Apr 05
2
line profiling
Hello,
This is about the new "line profiling" feature in R 3.0.0. As I was
testing it, I find the results somewhat disappointing so I'd like to
get your opinion.
I put some poorly written code in a test.R file, here are the contents:
double <- function(x) {
out <- c()
for (i in x) {
out <- c(out, 2*i) # line 4
}
return(out)
}
Then this how I source the file
2007 Oct 22
2
Help interpreting output of Rprof
Hello there,
I am not quite sure how to interpret the output of Rprof (in the following the output I was staring at). I was poking around the web a little bit for documentation but without much success. I guess if I want to figure out what takes so long in my code the 2nd table $by.total and the total.pct column (pct = percent) is the most helpful. What does it mean that [ or [.data.frame is
2009 Oct 19
2
how to get rid of 2 for-loops and optimize runtime
Short: get rid of the loops I use and optimize runtime
Dear all,
I want to calculate for each row the amount of the month ago. I use a matrix with 2100 rows and 22 colums (which is still a very small matrix. nrows of other matrixes can easily be more then 100000)
Table before
Year month quarter yearmonth Service ... Amount
2009 9 Q3 092009 A ...
2009 Jun 12
1
Rprof loses all system() time
Rprof seems to ignore all time spent inside system() calls. E.g.,
this simple example actually takes about 10 seconds, but Rprof thinks
the total time is only 0.12 seconds:
> Rprof("sleep-system.out") ; system.time(system(command="sleep 10")) ; Rprof(NULL)
user system elapsed
0.000 0.004 10.015
> summaryRprof("sleep-system.out")$by.total
2017 May 18
1
Interpreting R memory profiling statistics from Rprof() and gc()
Sorry, this might be a really basic question, but I'm trying to interpret
the results from memory profiling, and I have a few questions (marked by
*Q#*).
From the summaryRprof() documentation, it seems that the four columns of
statistics that are reported when setting memory.profiling=TRUE are
- vector memory in small blocks on the R heap
- vector memory in large blocks (from malloc)
- memory
2005 Jan 20
0
Interpreting Rprof output
Hello!
I have run Rprof on a function of mine and the results look very strange,
to say the least. At the end I of this email is an output of summaryRprof. Can someone help me interpret this output? I have read the appropriate section in the manual "Writing R Extensions" and help pages.
If I understand this output correctly, it is saying that "unlist" has been active in
2004 Oct 16
3
Lazy loading... advices
Hello,
I am looking for more information about lazy loading introduced in R 2.0.0.
Doing
?lazyLoad
I got some and there is a 'see also' section that points to
'makeLazyLoading'... But I cannot reach this page.
My problem is: I recompiled a library that uses a lot of functions from
other libraries (of course I can give details if needed). I load it in my
computer: library(svGUI),
2004 Oct 16
7
sapply and loop
Dear all,
I am doing 200 times simulation. For each time, I generate a matrix and
define some function on this matrix to get a 6 dimension vector as my
results.
As the loop should be slow, I generate 200 matrice first, and save them into
a list named ma,
then I define zz<-sapply(ma, myfunction)
To my surprise, It almost costs me the same time to get my results if I
directly use a loop
2004 Oct 16
7
sapply and loop
Dear all,
I am doing 200 times simulation. For each time, I generate a matrix and
define some function on this matrix to get a 6 dimension vector as my
results.
As the loop should be slow, I generate 200 matrice first, and save them into
a list named ma,
then I define zz<-sapply(ma, myfunction)
To my surprise, It almost costs me the same time to get my results if I
directly use a loop
2011 Feb 11
1
Help optimizing EMD::extrema()
Hi folks,
I'm attempting to use the EMD package to analyze some neuroimaging
data (timeseries with 64 channels sampled across 1 million time points
within each of 20 people). I found that processing a single channel of
data using EMD::emd() took about 8 hours. Exploration using Rprof()
suggested that most of the compute time was spent in EMD::extrema().
Looking at the code for EMD:extrema(),
2005 Oct 25
1
performance of nchar
Hi,
Is nchar function knowingly slow in R? I'm doing some string
formatting that requires multiple call to nchar, and nchar seems to be
very slow.
Experiment 1, pass nchar inside sprintf, and it takes 0.7 seconds
> system.time(for (i in 1:10000)
+ str = sprintf('0005%020d', nchar(op))
+ )[3]
[1] 0.7
Experiment 2, get the length of op separately using nchar, and then pass
2012 Jun 09
3
More simple implementation is slow.
Hi all.
I'm developing a function, which must return a square matrix.
Here is the code:
http://pastebin.com/THzEW9N7
These functions implement an analog of two embedded for cycles.
The first variant creates the resulting matrix by columns, cbind()-ing them
one by one.
The second variant creates the matrix with two columns, which rows contain
all possible
variants of i and j and calls apply
2012 Dec 05
1
Understanding svd usage and its necessity in generalized inverse calculation
Dear R-devel:
I could use some advice about matrix calculations and steps that might
make for faster computation of generalized inverses. It appears in
some projects there is a bottleneck at the use of svd in calculation
of generalized inverses.
Here's some Rprof output I need to understand.
> summaryRprof("Amelia.out")
$by.self
self.time self.pct
2010 Nov 17
1
efficient conversion of matrix column rows to list elements
Hi List,
I'm hoping to get opinions for enhancing the efficiency of the following
code designed to take a vector of probabilities (outcomes) and calculate a
union of the probability space. As part of the union calculation, combn()
must be used, which returns a matrix, and the parallelized version of
lapply() provided in the multicore package requires a list. I've found that
2010 Nov 19
1
memory profiling
I'm trying to configure Version 2.12.0 or R to do memory profiling.
I've reconfigured the code:
% ./compile --enable-memory-profiling=YES
and verified that it's configured correctly by examining the output. I then
rebuild R:
% make
Then I fire up R and run a script, using Rprof with the memory-profiling
switch set to TRUE:
Rprof("output", memory.profiling=TRUE);
# a
2010 Jan 05
1
Naming functions for the purpose of profiling
Hi all,
I have some long-running code that I'm trying to profile. I am seeing a
lot of time spent inside the <Anonymous> function. Of course, this can
in fact be any of several functions, but I am unable to see how I could
use the information from Rprof.out to discern which function is taking
the most time. An example line from my Rprof.out is:
rbernoulli <Anonymous>