similar to: Memory Efficiency of Symmetric Matrix

Displaying 20 results from an estimated 1000 matches similar to: "Memory Efficiency of Symmetric Matrix"

2009 Jan 12
4
fitting curve to data
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I have the following data: > y [1] 0.000 0.004 0.008 0.016 0.024 0.032 0.044 0.064 0.072 0.088 0.108 0.140 [13] 0.156 0.180 0.208 0.236 0.264 0.296 0.320 0.360 0.408 0.444 0.472 0.524 [25] 0.576 > x [1] 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 [16] 1600 1700 1800 1900 2000 2100 2200 2300 2400 2500 I'd
2009 Jun 17
1
Coerce rectangular matrix to symmetrical square matrix
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I have a rectangular matrix of size 920 by 85. I'd like to coerce it into a square matrix such that all row/col names are present in the new matrix and the additional values are zero. As an example: A B C D A 1 2 3 4 E 5 6 7 8 F 9 10 11 12 Would be coerced to: A B C D E F A 1 2 3 4 5 9 B 2 0 0 0 6 10 C 3 0 0
2009 May 29
1
Package Licences
Are there any particular licences under which R packages must be released or is it the discretion of the author? The same question if the package is to be destined for CRAN? Kind regards, Nathan -- -------------------------------------------------------- Dr. Nathan S. Watson-Haigh OCE Post Doctoral Fellow CSIRO Livestock Industries Queensland Bioscience Precinct St Lucia, QLD 4067 Australia
2009 Feb 17
1
Create package with Fortran 90 and C code
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I'm trying to add some Fortran 90 code to an existing package. When I compile and load the file manually like: SHELL> R CMD SHLIB file.f90 R> dyn.load("file.so") I can use the .Fortran() fine. However, when I try to build, install and load the library I seem to be missing something. I do a: SHELL> R CMD build dir SHELL> R
2009 Feb 11
1
Looping over a matrix passed to .C
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I've written a function in R which takes a symmetrical matrix as input and processes all triplicate combinations of values from the matrix. The function looks something like: my_fun <- function(m) { if( nrow(mat) != ncol(mat) ) { stop("'m' must be a square matrix") } size <- nrow(m) for(x in 1:(size -2)) {
2009 Feb 03
1
pairs() help - colour histograms on diagonal
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I'd like to be able to colour histograms along the diagonal using the colours stored in colnames(d): > d black blue brown cyan 1 0.96405751 -0.02964390 -0.060147424 -0.06460070 2 -0.03614607 0.95475444 -0.152382053 -0.07767974 3 -0.07095613 -0.05884884 -0.061289399 -0.06445973 4 -0.03708223 -0.05997624
2009 Jan 15
2
R package tests
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I was wondering if anyone could point me in the right direction for reading up on writing tests in R. I'm writing some functions for inclusion into a package and would like to test them to ensure they're doing what I expect them to do. Are these approaches used for testing packages in CRAN? Cheers, Nathan - -- -
2009 Jan 07
2
Understanding dsyrk_ in C code
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I'm trying to understand some C code in an R package I'm using. I'm address this question here as it's matrix algebra...and I'm no pro at that! the C command reads: double alpha = 1.0, beta = 0.0; dsyrk_("L", "N", nGenes, nGenes, & alpha, mat1, nGenes, & beta, mat2, nGenes); - From google,
2009 Mar 26
1
Splitting Area under curve into equal portions
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I have some data generated as follows: <code> n <- 2000 work <- vector() for(x in 1:n) { work[x] <- sum(1:(n-x+1)) } plot(work) </code> What I want to do - ----------------- I want to split work into a number of unequal chunks such that the sum of the values in each chunk is approximately equal. The numbers in
2008 Dec 15
1
Pearson Correlation Speed
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I'm trying to calculate Pearson correlation coefficients for a large matrix of size 18563 x 18563. The following function takes about XX minutes to complete, and I'd like to do this calculation about 15 times and so speed is some what of an issue. Does anyone have any suggestions on ways to speed this up? I'd wondered if using C++ code to
2009 Jun 14
1
Identifying clusters of size n
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Is there a library which is capable of identifying distinct clusters of size n from a series of XY coordinates? Failing this, I'd like to be able to to something like: Using a sliding window of size n along the x-axis I'd like to determine the distance between the center of the points in the window and the closest point outside the window. I
2009 Jul 09
1
Converting indices of a matrix subset
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I have two matrices: > m1 <- matrix(1,4,4) > m1 [,1] [,2] [,3] [,4] [1,] 1 1 1 1 [2,] 1 1 1 1 [3,] 1 1 1 1 [4,] 1 1 1 1 > m2 <- matrix(0,3,3) > diag(m2) <- 1 > m2 [,1] [,2] [,3] [1,] 1 0 0 [2,] 0 1 0 [3,] 0 0 1 I want to get indicies from m2
2009 Jan 14
3
Precision in R
Dear All, I'm preparing a simple algorithm for matrix multiplication for a specific purpose, but I'm getting some unexpected results. If anyone could give a clue, I would really appreciate. Basically what I want to do is a simple matrix multiplication: (WB) %*% t(WB). The WB is in the disk so I compared to approaches: - Load 'WB' using 'read.table' (put it in WB.tmp) and
2010 Jan 27
2
Bulk Match/Replace
This must be easy to do..... I have a vector and a lookup data.frame: > v [1] "5" "234" "234" "42-43" "234" "42-43" "234" "234" "42-43" "234" "5" "234" "234" "5" "234" "234" "5"
2010 Feb 08
2
Help with apply()
I have a 2 column data.frame: > d[1:5,] a b 1 80015 C 2 80016 B 3 80023 C 4 80062 B 5 80069 B I want to apply a function across each row: > for(i in 1:nrow(d)) { + myFun(con, d[i,]$a, d[i,]$b) + } How do I do this using apply()? I'm unsure how to tell apply() to pass data from columns a and b for a given row as arguments to the function
2010 Jan 25
1
RMySQL Append data.frame to table
I have a data.frame obj with 5 columns whose colnames match the fields in my "contact" table. The only other field my MySQL table has is an id field which is the PK and is set to auto increment. I'd like to load this data.frame using something like: dbWriteTable(con, "contact", dat, append=TRUE) However, I get this error: Error in mysqlExecStatement(conn, statement,
2010 Jan 13
1
decompress tar.gz and zip files
Can anyone point me in the right direction for decompressing text files that are compressed as tar.gz or zip files? Cheers, Nathan -- -------------------------------------------------------- Dr. Nathan S. Watson-Haigh OCE Post Doctoral Fellow CSIRO Livestock Industries University Drive Townsville, QLD 4810 Australia Tel: +61 (0)7 4753 8548 Fax: +61 (0)7 4753 8600 Web:
2010 Mar 18
1
Intersect, Union of date/time ranges
I have 2 sets of data which defines the start and end of date/time periods. I want to be able to obtain the following: 1) The intersect of those 2 sets of date/time ranges i.e. return start/end date/time ranges where both sets overlap 2) The union of those 2 sets of date/time ranges i.e. return the start/end date/time ranges which are in 1 or both sets Is there anything that is currently able
2009 Mar 25
0
Rmpi - send/receive multiple objects to slaves
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I've written a function that uses Rmpi to perform a calculation in parallel. It works fine, but I'm trying to improve efficiency in terms of memory usage and the amount of data being passed back and forth between mater and slaves. Calculations are performed on a symmetrical matrix in order to zero-out some of the cells. In the parallel
2010 Jan 27
2
RMySQL - Bulk loading data and creating FK links
I have a table (contact) with several fields and it's PK is an auto increment field. I'm bulk loading data to this table from files which if successful will be about 3.5million rows (approx 16000 rows per file). However, I have a linking table (an_contact) to resolve a m:m relationship between the an and contact tables. How can I retrieve the PK's for the data bulk loaded into