similar to: help with table partition

Displaying 20 results from an estimated 6000 matches similar to: "help with table partition"

2006 Jun 15
0
log returns (was: Re: help with table partition)
Please use a descriptive subject and not tag onto a prior thread for new topics. Assuming the first row is time 1 and the second row is time 2 and so on try: diff(log(P)) On 6/15/06, Wong, Kim <kwong at nymex.com> wrote: > > Hi, thank you all for the help. > > The split function works very well. > > I have an additional question. If I have a matrix of prices (row = 30,
2007 Nov 13
2
Query an Access database based on a date attribute (Tudor Bodea)
Tudor Bodea asked: >In this context, I try to get all the records for which market is atl-bos, >competitor is delta and dd is 2007-11-20 (first record above). To do this I used >># channel <- odbcConnectAccess("test.mdb") >>res <- sqlQuery(channel, "select * from test_table where market = 'atl-bos' >>and competitor = 'delta' and dd =
2007 Nov 13
1
R: Query an Access database based on a date attribute
It seems that Access needs that you surround the dates with a # symbol. You probably need something like. res <- sqlQuery(channel, "select * from test_table where market = 'atl-bos' and competitor = 'delta' and dd = #2007-11-20#") Hope this helps, Stefano -----Messaggio originale----- Da: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org]Per
2007 Nov 12
2
Query an Access database based on a date attribute
Dear useRs, I would like to query an Access database through R based on a date attribute but, unfortunately, I fail to do so. For example, the table test_table of the test.mdb looks like: ID cd market competitor dd price 1 1 2007-11-20 atl-bos delta 2007-11-20 210 2 2 2007-11-20 atl-bos delta 2007-11-21 190 3 3 2007-11-20 atl-bos delta 2007-11-22
2013 Aug 09
1
a fast table() for the 1D case
Hi, table1D() below can be up to 60x faster than base::table() for the 1D case. Here are the detailed speedups compared to base::table(). o With a logical vector of length 5M: 11x faster (or more if 'useNA="always"') o With factor/integer/numeric/character of length 1M and 9 levels (or 9 distinct values for non-factors):
2006 Feb 27
1
rails activerecord
i found model allway query this sql: SHOW FIELDS FROM test_table if my code needn''t know table structure, how to remove it? -- Posted via http://www.ruby-forum.com/.
2012 Oct 22
4
Help with applying a function to all possible 2x2 submatrices
Hi all, I'm working with a large data set (on the order of 300X300) and trying to apply a function which compares the elements of all possible 2x2 submatrices. There are rc(r-1)(c-1) such submatrices, so obviously the naive method of looping through the rows and columns is computationally unfeasible for my data set: for(i in 1:(nrow(data)-1)) { for(j in (i+1):nrow(data)) { for (m
2012 Feb 10
2
Split matrix into square submatices
Hi everybody, I'm looking for an optimal way to split a big matrix (e.g. ncol = 8, nrow=8) into small square submatrices (e.g. ncol=2, nrow=2) For example If I have > h [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [1,] 1 9 17 25 33 41 49 57 [2,] 2 10 18 26 34 42 50 58 [3,] 3 11 19 27 35 43 51 59 [4,] 4 12 20 28 36
2004 Sep 15
2
efficient submatrix extraction
Hi, I have a matrix of say 1024x1024 and I want to look at it in chunks. That is I'd like to divide into a series of submatrices of order 2x2. | 1 2 3 4 5 6 7 8 ... | | 1 2 3 4 5 6 7 8 ... | | 1 2 3 4 5 6 7 8 ... | | 1 2 3 4 5 6 7 8 ... | ... So the first submatrix would be | 1 2 | | 1 2 | the second one would be | 3 4 | | 3 4 | and so on. That is I want the matrix to be evenly divided
2015 Oct 28
3
Extraer elementos diagonales de submatrices
Estimado Javier, Gracias por tu mensaje. No, lo unico que requiero es la lista de números (i1, 2, 3, 1, 2, 3, 4, 5, 1, 2). Saludos cordiales, Jorge.- 2015-10-28 14:35 GMT-05:00 Javier Rubén Marcuzzi < javier.ruben.marcuzzi en gmail.com>: > Estimado Jorge I Velez > > > > No comprendo un punto, dices que deseas construir sub matrices y extraer > elementos de sub
2015 Oct 29
2
Extraer elementos diagonales de submatrices
El código que me olvide pegar input m <- structure(c(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 0, 0, 0, 0, 0, 4, 4, 4, 4, 4, 0, 0, 0, 0, 0, 0, 0, 5, 5, 5), .Dim = c(10L, 5L)) m ## output output <- c(1:3, 1:5, 1:2) output nfilas <- nrow(m) while(nfilas > 0) { diagonal <- diag(m)
2012 Oct 30
2
Put submatrices in an array
Dear R users, I have a Hadamard matrix 16x15 and i want to put 16x5 submatrices in an array put i have an error. > A1<-matrix(c(0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, + 1,0,1,0,1,0,1,0,1,0,1,0,1,0,1, + 0,1,1,0,0,1,1,0,0,1,1,0,0,1,1, + 1,1,0,0,1,1,0,0,1,1,0,0,1,1,0, + 0,0,0,1,1,1,1,0,0,0,0,1,1,1,1, + 1,0,1,1,0,1,0,0,1,0,1,1,0,1,0, + 0,1,1,1,1,0,0,0,0,1,1,1,1,0,0, + 1,1,0,1,0,0,1,0,1,1,0,1,0,0,1, +
2015 Oct 28
2
Extraer elementos diagonales de submatrices
Buenos dias a todos, Quisiera extraer algunas entradas de una matrix "m" teniendo en cuenta algunas restricciones. El siguiente ejemplo ilustra la situacion: ## input m <- structure(c(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 0, 0, 0, 0, 0, 4, 4, 4, 4, 4, 0, 0, 0, 0, 0, 0, 0, 5, 5, 5), .Dim = c(10L, 5L)) m ## output output <-
2006 Jun 19
2
Nested variance-covariance matrix in Multilevel model
Dear R community, I have trouble implementing a nested variance-covariance matrix in the lme function. The model has two fixed effects called End and logpgc, the response variable is the logarithm to base 2 of Intensity ( log2(Intensity) ) and the random effects are called Probe and ProbeNo. The model has the following nesting structure: A Pixel is nested within the ProbeNo,the ProbeNo is
2012 Jul 31
1
ways of getting around allocMatrix limit?
I need to multiply to very large, nonsparse matrices, and so get the error "allocMatrix: too many elements specified". Is there a way to set the limit for allocMatrix? In my case, the two matrices, A and B, are nxm and mxp where m is small, so I could subdivide each into blocks of submatrices A=rbind(A1,A2,...) and B=cbind(B1,B2,...) then multiply each pair of submatrices, but I was
2012 Aug 23
1
Why was my R process killed spontaneously?
I tried to use gpuCor function in the gputools package of R to calcuate the pairwise correlations of a matrix of 40,000 columns. Becuase there would be memory issues if I use the whole matrix at a time, I splitted the matrix into submatrix of 10,000 columns and then calculate the pairwise correlation of different submatrices. There are altogether 4 submatrices, so I need to calculate the pearson
2017 Oct 13
2
How to define proper breaks in RFM analysis
> On Oct 13, 2017, at 2:51 AM, PIKAL Petr <petr.pikal at precheza.cz> wrote: > > Hi > > You expect us to solve your problem but you ignore advice already recieved. > > Your data are unreadable, use dput(yourdata) instead. see ?dput > >> test<-read.table("clipboard", heade=T) > Error in scan(file = file, what = what, sep = sep, quote = quote,
2002 Feb 01
3
matrix with ncol=1
Hello list, I try to optimize some R code and it turns out that the function as.matrix takes a lot of time in my code. There is only one reason why I need as.matrix: My code should work for matrices with ncol=p and p should be allowed to be 1 or larger. Now I have a matrix x with dim(x)=(n,p), and I need to work with the submatrix y <-x[gv,], (gv a vector of n logicals) and to calculate
2011 Apr 27
2
sub-matrix block size
Dear Rxperts Below is a small vector of values of zeros and non-zeros... was wondering if there is an efficient way to get the block sizes of submatrices of a big matrix similar to the one shown below? diagonal elements can be zero too. Rows with only a diagonal element may be considered as a unit block size. c(1,0,0,0,0,0,0,0,0,0,0, 1,1,0,0,0,0,0,0,0,0,0, 0,0,1,0,0,0,0,0,0,0,0,
2011 Aug 21
1
How can I divide an image and randomly plot the segements
Hi! I would like to divide a 401 by 401 image into 20 equal blocks and then re-plot the image with the segments randomly distributed in it. How can I do this? ............. Regards, Kenduiywo Benson [[alternative HTML version deleted]]