Displaying 15 results from an estimated 15 matches for "mergesort".
2016 Apr 19
2
Merge sort
Hello everyone,
I am learning R since recently, and as a small exercise I wanted to
write a recursive mergesort. I was extremely surprised to discover that
my sorting, although operational, is deeply inefficient in time. Here is
my code :
> merge <- function(x,y){
> if (is.na(x[1])) return(y)
> else if (is.na(y[1])) return(x)
> else if (x[1]<y[1]) return(c(x[1],merge(x[-1],y)))
>...
2016 Apr 19
0
Merge sort
On 19/04/2016 3:39 PM, Gaston wrote:
> Hello everyone,
>
> I am learning R since recently, and as a small exercise I wanted to
> write a recursive mergesort. I was extremely surprised to discover that
> my sorting, although operational, is deeply inefficient in time. Here is
> my code :
>
>> merge <- function(x,y){
>> if (is.na(x[1])) return(y)
>> else if (is.na(y[1])) return(x)
>> else if (x[1]<y[1]) ret...
2016 Apr 20
1
Merge sort
...reassigning and copying?) is also expensive.
Thank you for your help!
On 04/19/2016 11:51 PM, Duncan Murdoch wrote:
> On 19/04/2016 3:39 PM, Gaston wrote:
>> Hello everyone,
>>
>> I am learning R since recently, and as a small exercise I wanted to
>> write a recursive mergesort. I was extremely surprised to discover that
>> my sorting, although operational, is deeply inefficient in time. Here is
>> my code :
>>
>>> merge <- function(x,y){
>>> if (is.na(x[1])) return(y)
>>> else if (is.na(y[1])) return(x)
>>>...
2004 Aug 25
4
bugfix: indeterministic file choice from multiple sources
...not guarantee the former order, if items to sort have the same value. Our
test case triggers a situation where this unstabilibity shows up.
Why does it not happen in gnu linux versions?
Reading man pages showed us that glibc has an "optimization" in qsort: if
memory is not low it uses mergesort instead, which is a stable sort
algorithm.
fix:
Since in our scenario using rsync we rely on deterministic behaviour, we
patched rsync to use mergesort always for composing the file list. For
systems without a mergesort system call (most os's except freebsd/darwin)
we use the freebsd impl...
2020 Aug 19
2
[Bug 1450] New: Using certain simple set combinations with TCP flags causes error in mergesort.c from nft list ruleset
https://bugzilla.netfilter.org/show_bug.cgi?id=1450
Bug ID: 1450
Summary: Using certain simple set combinations with TCP flags
causes error in mergesort.c from nft list ruleset
Product: nftables
Version: unspecified
Hardware: arm
OS: Ubuntu
Status: NEW
Severity: normal
Priority: P5
Component: nft
Assignee: pablo at netfilter.org
Reporter: ph...
2006 Jun 02
3
[PATCH] --omit-dir-changes, qsort<>mergesort issues
...st I would sleep a lot
better if there's a sure method not set directory permission/ownership.
I'd love to hear any feedback about the patch or if doesn't work correctly
in some scenario.
Cheers,
-Antti
[1] Reliable sync from multiple src roots requires a custom build of rsync
with mergesort() built-in. I'm having the same problem as discussed
in thread at http://lists.samba.org/archive/rsync/2004-August/010398.html
and http://lists.samba.org/archive/rsync/2003-November/007756.html.
There's another qsort<>mergesort testing tool available at
http://www.hut.fi/~aet/test-r...
2005 Jun 09
1
handling duplicate names deterministically and adding alternative checksum algorithms
Thanks, rsync developers, for creating such a great tool.
I'm a member of a team of system administrators and integrators that
use rsync with SystemImager and Cfengine to rapidly deploy and
prescriptively maintain systems. Our current practices would benefit
if rsync were enhanced to handle duplicate names deterministically as
described in the todo list. If we were able to use rsync to
2020 Oct 27
0
[ANNOUNCE] nftables 0.9.7 release
...on
netlink_delinearize: transform binary operation to prefix only with values
evaluate: disregard ct address matching without family
segtree: memleaks in interval_map_decompose()
src: cache gets out of sync in interactive mode
src: add comment support for map too
mergesort: unbreak listing with binops
src: add expression handler hashtable
src: add chain hashtable cache
mergesort: find base value expression type via recursion
mnl: larger receive socket buffer for netlink errors
tests: py: flush log file output before running each command...
2024 Sep 23
0
bit, bit64, ff and greeNsort
...eloping more sustainable sorting algorithms that provide better
trade-offs between memory investments, compute costs and adaptivity to
easier input patterns. My R&D project was successfully completed 2024
with theory and design of new symmetric sorting algorithms that can
replace Quicksort, Mergesort and Timsort. Lots of info at greeNsort.org.
I have an R package `greeNsort` on github with a research testbed that
can measure RAM, CPU and RAPL energy for ?150 equally tuned sorting
algorithms on multiple test patterns.
Since 24.2.2022 my priorities are on strengthening resilience of
European...
2024 Sep 23
0
bit, bit64, ff and greeNsort
...eloping more sustainable sorting algorithms that provide better
trade-offs between memory investments, compute costs and adaptivity to
easier input patterns. My R&D project was successfully completed 2024
with theory and design of new symmetric sorting algorithms that can
replace Quicksort, Mergesort and Timsort. Lots of info at greeNsort.org.
I have an R package `greeNsort` on github with a research testbed that
can measure RAM, CPU and RAPL energy for ?150 equally tuned sorting
algorithms on multiple test patterns.
Since 24.2.2022 my priorities are on strengthening resilience of
European...
2008 Feb 01
0
rsync Digest, Vol 62, Issue 1
...ibrary implementation and the order of directory entries in the source (which in turn is sensitive to the filesystem implementation). You probably have both a different C library and a different filesystem than I do.
In any case, since rsync 3.0.0pre1, the default file-list sorting algorithm is a mergesort, which is stable, so files from earlier source arguments take priority. If you upgrade to an rsync 3.0.0pre* version, your scenario should work consistently. If it doesn't, that's a bug we should try to fix.
Matt
------------------------------
Message: 4
Date: Fri, 1 Feb 2008 09:46:4...
2008 Oct 08
4
question from Braun/Murdoch book
Hi R People:
I am looking at the Braun/Murdoch book, " A First Course in
Statistical Programming in R", and I have a question about a function
there. It's on page 52, Example 4.5; the sieve of Erastosthenes.
There is a line:
primes <- c()
Is there a difference between using that and
primes <- NULL
please?
When you put in primes <- c(), primes comes back as NULL.
Is
2003 Apr 02
1
bug report: bus error on Mac OS/X 10.2.3
...2.4 (Build 6I32)
Host: Albus.local.
Command: rsync
PID: 2349
Exception: EXC_BAD_ACCESS (0x0001)
Codes: KERN_PROTECTION_FAILURE (0x0002) at 0x00000008
Thread 0 Crashed:
#0 0x90004fb0 in strcmp
#1 0x9001b2d0 in insertionsort
#2 0x9001afc0 in setup
#3 0x9001aa98 in mergesort
#4 0x9000b968 in __opendir2
#5 0x00010620 in 0x10620
#6 0x000105dc in 0x105dc
#7 0x00010804 in 0x10804
#8 0x000105dc in 0x105dc
#9 0x00010804 in 0x10804
#10 0x000105dc in 0x105dc
#11 0x00010804 in 0x10804
#12 0x000105dc in 0x105dc
#13 0x00010c28 in 0x10c28
#14 0x00009d64...
2010 May 21
0
Wine release 1.2-rc1
...qtz32: Add support for MCI_STATUS_TIME_FORMAT.
mciqtz32: Add support for MCI_PAUSE.
Marcus Meissner (7):
ole32: Fixed 2 uninitialized variable use (Coverity).
wined3d: fixed a NULL deref in create_arb_blt_fragment_program (Coverity).
ntdll: Reimplement qsort() using generic mergesort.
ntdll: Rename mergesort to NTDLL_mergesort.
ntdll: Implement bsearch, lfind to use correct comparator functions.
msvcrt: Add some missing CDECL.
msvcrt: Check locale for NULL before freeing.
Matej ?pindler (11):
winecfg: Update Slovenian translation.
shell32: U...
2024 Jul 16
0
[ANNOUNCE] nftables 1.1.0 release
...objects
tests: shell: Add missing json-nft dumps
tests: shell: Fix one json-nft dump for reordered output
doc: libnftables-json: Drop invalid ops from match expression
doc: nft.8: Two minor synopsis fixups
json: Accept more than two operands in binary expressions
mergesort: Avoid accidental set element reordering
tests: py: Fix some JSON equivalents
tests: py: Warn if recorded JSON output matches the input
tests: py: Drop needless recorded JSON outputs
tests: shell: Avoid escape chars when printing to non-terminals
Add support for table&...