Displaying 20 results from an estimated 10000 matches similar to: "Finding a basis in a set of vectors"
2009 Jan 12
1
Loading workspaces from the command line
Hi,
Is there any way to load workspaces (e.g. stuff from save.image) from
the command line? I'm on Linux, and would find this very helpful.
I'm guessing this functionality can be duplicated with a skillful bash
script to rename the particular file to .RData (and then back once R
terminates), but I'm wondering if there's a better way.
Zhou Fang
2009 May 28
2
Replace is leaking?
Okay, someone explain this behaviour to me:
Browse[1]> replace(rep(0, 4000), temp1[12] , temp2[12])[3925]
[1] 0.4462404
Browse[1]> temp1[12]
[1] 3926
Browse[1]> temp2[12]
[1] 0.4462404
Browse[1]> replace(rep(0, 4000), 3926 , temp2[12])[3925]
[1] 0
For some reason, R seems to shift indices along when doing this replacement.
Has anyone encountered this bug before? It seems to crop up
2009 Feb 15
2
Fast ave for sorted data?
Hi,
This is probably really obvious, by I can't seem to find anything on it.
Is there a fast version of ave for when the data is already sorted in
terms of the factor, or if the breaks are already known?
Basically, I have:
X = 0.1, 0.2, 0.32, 0.32, 0.4, 0.56, 0.56, 0.7...
Y = 223, 434, 343, 544, 231.... etc
of the same, admittedly large length.
Now note that some of the values of X are
2008 Jan 20
1
Looping over subsets
Hi,
Possibly a dumb question, but I wonder if anyone can help me with this.
What I want to do, essentially, is to loop over all ordered subsets of a
given size of a certain set. Ultimately, the idea is to find the subset
that maximises a certain value.
The set in question is likely large (the subset size is likely small,
though), so things like combn don't seem to be a good solution. The
2012 May 08
1
Fast reading of hex data?
Hi all,
Basically, I have data in the format of (up to 1 gig in size) text files
containing stuff like:
F34060F81000F28055F8A000F2E05EF8F000F34 (...)
The data is basically strings denoting hex values (9 = 9, A = 10, B = 11,
...) organised in fixed, small blocks. What I want to do is to read in a
specified segment of the string, break it up into blocks, and convert it
into a vector of integers
2004 Jul 01
1
QR decomposition question
Hi all,
I wonder if this kind of questions are ok in this
list...
Quick question:
What does it mean than the rank of the QR
decomposition of a NxN matrix is N-1 ?
m: NxN matrix
qr(m)$rank equal to (N-1)
Long version:
I'm doing a manova on a matrix of 10 variables
and 16 observations.
> dim(tmp)
[1] 16 10
> fit <- manova( tmp ~ treatment*mouse )
>results <-
2018 Jan 22
3
Inconsistent rank in qr()
Le 22/01/2018 ? 17:40, Keith O'Hara a ?crit?:
> This behavior is noted in the qr documentation, no?
>
> rank - the rank of x as computed by the decomposition(*): always full rank in the LAPACK case.
For a me a "full rank matrix" is a matrix the rank of which is indeed min(nrow(A), ncol(A))
but here the meaning of "always is full rank" is somewhat confusing. Does it
2008 Oct 22
1
Inserting blank lines into a file
Hi,
Should be a quickie:
I want to make a datafile in R for plotting in gnuplot (which has
friendlier 3D plotting options, as far as I can tell). So, I want to
create a file with contents along the lines of
#File begins
0 0 10
0 13 10
0.2 2 10
1 0 10.12
1 1 5
1 2 10
2 0 10
2 1 1
2 2 10
It's probably fairly easy to write the space-separated numbers with
write.table, sink, or similar. But
2018 Jan 23
1
Inconsistent rank in qr()
Le 23/01/2018 ? 08:47, Martin Maechler a ?crit?:
>>>>>> Serguei Sokol <sokol at insa-toulouse.fr>
>>>>>> on Mon, 22 Jan 2018 17:57:47 +0100 writes:
> > Le 22/01/2018 ? 17:40, Keith O'Hara a ?crit?:
> >> This behavior is noted in the qr documentation, no?
> >>
> >> rank - the rank of x as
2004 Mar 05
1
row-echelon form (was no subject)
I think one needs an LU decomposition rather than QR.
However, I couldn't find anything off the shelf to do
an LU, other than learning that determinant() now
uses LU instead of QR or SVD, so the code to do it must
be in there for those that want it.
You'll probably need to divide rows of U by the first
entry if you insist on the unique reduced REF.
However, I can't see any reason
2013 Jul 27
1
[LLVMdev] arch-specific predefines in LLVM's source
Hi,
> ----- Original Message -----
>>> ----- Original Message -----
>>>> Hi all,
>>>> My recent commit r187027 fixed a simple oversight of forgetting
>>>> to
>>>> check for __ppc__ (only checking __powerpc__), which broke my
>>>> powerpc-apple-darwin8 stage1 tests, since the system gcc only
>>>> provided
2004 Apr 30
1
calculation of U and V matrix of SVD decomposition (according to LINPACK, X = UDV')
Hello,
Like QR decomposition, I am looking for decomposition to get U and V matrix
of SVD decomposition (according to LINPACK, X = UDV'). Do you know if there
is a function which could calculate this decomposition?
Look forward to your reply,
Haleh
2003 Aug 13
3
A question on orthogonal basis vectors
Hey, R-listers,
I have a question about determining the orthogonal
basis vectors.
In the d-dimensinonal space, if I already know
the first r orthogonal basis vectors, should I be
able to determine the remaining d-r orthognal basis
vectors automatically?
Or the answer is not unique?
Thanks for your attention.
Fred
2012 Jan 17
2
[LLVMdev] powerpc-darwin8 build/test status page
Hi,
For anyone who might be interested, I've thrown together a little
page to track my builds of llvm and clang, both release 3.0 and
svn-trunk, on powerpc-darwin8.
http://www.csl.cornell.edu/~fang/sw/llvm/
I'll update the list of logs each time I svn-update and build. It's
nowhere as nice as a real buildbot page, but it's better than nothing.
3.0 still has over 20 test
2013 Jul 26
2
[LLVMdev] arch-specific predefines in LLVM's source
> ----- Original Message -----
>> Hi all,
>> My recent commit r187027 fixed a simple oversight of forgetting to
>> check for __ppc__ (only checking __powerpc__), which broke my
>> powerpc-apple-darwin8 stage1 tests, since the system gcc only
>> provided
>> __ppc__. I was wondering if this justifies using simpler macros like
>>
>> #define
2013 Jul 27
0
[LLVMdev] arch-specific predefines in LLVM's source
----- Original Message -----
> > ----- Original Message -----
> >> Hi all,
> >> My recent commit r187027 fixed a simple oversight of forgetting
> >> to
> >> check for __ppc__ (only checking __powerpc__), which broke my
> >> powerpc-apple-darwin8 stage1 tests, since the system gcc only
> >> provided
> >> __ppc__. I was
2011 Dec 16
3
[LLVMdev] llvm/clang test failures on powerpc-darwin8
Hi,
Thanks for the quick reply again.
> On Thu, Dec 15, 2011 at 1:17 PM, David Fang <fang at csl.cornell.edu> wrote:
>> Hi,
>>
>> I've bootstrapped llvm/clang from svn-trunk on powerpc-darwin8 (g++-4.0.1), and
>> have the following test results to share.
>> Summary below, full log at:
>>
2012 Jan 18
1
[LLVMdev] [cfe-dev] powerpc-darwin8 build/test status page
18.01.2012, 02:46, "David Fang" <fang at csl.cornell.edu>:
> Hi,
> For anyone who might be interested, I've thrown together a little
> page to track my builds of llvm and clang, both release 3.0 and
> svn-trunk, on powerpc-darwin8.
>
> http://www.csl.cornell.edu/~fang/sw/llvm/
>
> I'll update the list of logs each time I svn-update and
2012 Jan 18
0
[LLVMdev] [cfe-dev] powerpc-darwin8 build/test status page
On Wed, Jan 18, 2012 at 10:51:38PM +0400, Konstantin Tokarev wrote:
>
>
> 18.01.2012, 02:46, "David Fang" <fang at csl.cornell.edu>:
> > Hi,
> > ?????????For anyone who might be interested, I've thrown together a little
> > page to track my builds of llvm and clang, both release 3.0 and
> > svn-trunk, on powerpc-darwin8.
> >
> >
2020 Jun 02
2
Improve hot cold splitting to aggressively outline small blocks
Hello Tobias,
Thank you for the suggestion! Aditya also mentioned this. I will look into
it.
Best regards,
Ruijie
Ruijie Fang
Email: ruijief at princeton.edu
On Tue, Jun 2, 2020 at 12:48 PM Tobias Hieta <tobias at plexapp.com> wrote:
> Hello Ruijie,
>
> One other workload that would be interesting to test might be clang
> itself. Building clang with PGO information is a