similar to: 3d matrix * 1d matrix question

Dear R-users, I am working on a problem that I am currently not able to solve efficiently. It is about multiplying one column of a matrix with only a certain number of rows of another matrix. Let me illustrate my problem with an example: n.obs = 800 n.rowsperobs = 300 n.param = 23 Designmat = matrix(rnorm(n.obs*n.rowsperobs*n.param),ncol=n.param) Betamat =

I am having a hard time understanding just what 'sweep' does. The documentation states: Return an array obtained from an input array by sweeping out a summary statistic. So what does it mean "weeping out a summary statistic"? Thank you. Kevin

is there a way to do element-by-element multiplication as in Gauss and MATLAB, as shown below? Thanks. --- a 1.0000000 2.0000000 3.0000000 x 1.0000000 2.0000000 3.0000000 2.0000000 4.0000000 6.0000000 3.0000000 6.0000000 9.0000000 a.*x 1.0000000 2.0000000 3.0000000 4.0000000

I am trying to multiply a 3D array of 4x4x4 by the 4 3D arrays of a 4D array with dimensions 4x4x4x4 (the last dimension being the one that I want to split by). (4x4x4 array) > hiaAry , , a1 i1 i2 i3 i4 h1 9.5936098 6.001040 0.08772 0.3138600 h2 1.2003500 1.454570 2.79248 0.0000000 h3 0.1346500 0.201220 0.39256 0.5464000 h4 0.0109000 0.012270 0.16417 0.2766900 ,

Dear R helpers Suppose x  <- c(1:3) y  <- matrix(1:12, ncol = 3, nrow = 4) > y      [,1] [,2] [,3] [1,]    1    5    9 [2,]    2    6   10 [3,]    3    7   11 [4,]    4    8   12 I wish to multiply 1st column of y by first element of x i.e. 1, 2nd column of y by 2nd element of x i.e. 2 an so on. Thus the resultant matrix should be like > z      [,1]   [,2]    [,3] [1,]    1   

Say I have two matrixes: one is 8x28 and other 8x8 I'd like to multiply, for example, first and second column from the 8x8 and plant them in first column of 8x28. Then take first and third of 8x8 and plant into second column of 8x28.etc. Any ideas? Thanks! [[alternative HTML version deleted]]

I am sure there is a simple solution to this... I have a column in a data frame specifying a grouping (1, -1) for my observations, and need to mutliply each observation in all the other columns of the data frame by the corresponding value in the given column. I played with apply, and saw some suggestions for sweep, but did not manage to get it working. My table contains NAs.... Example of

On 8/3/07 22:12, "Gad Abraham" <g.abraham at ms.unimelb.edu.au> wrote: > Laura Hill wrote: >> >> >> On 7/3/07 00:15, "Gad Abraham" <g.abraham at ms.unimelb.edu.au> wrote: >> >>>> On 6 Mar 2007, at 08:54, Laura Hill wrote: >>>> >>>>> Hi, >>>>> >>>>> My name is

I have a big matrix 'ret'. I want to multiply each row of it with a 2nd vector 'pos', resulting result, I want to save in a vector named 'port'. I wrote following code: > pos [1] 2593419 2130220 6198197 1673888 1980000 1784732 2052120 -7490228 -5275000 > dim(ret) [1] 500 9 > fu # user defined function function(x) { fu = x %*%

I don't think the global fast math flag should override the NoContraction decoration as that's mostly the point of that decoration to begin with, to have fine granular control while still having a broad sweeping optimization. Did I miss your point? I feel like I did. On Thu, Aug 23, 2018, 3:42 PM Michael Berg <michael_c_berg at apple.com> wrote: > Ryan, > > Given that the

Hi all, To get wider visibility, build a broader consensus and address concerns on this topic, I'm again raising this as an RFC. This is a proposal to change the rule for variable names from CamelCase to camelBack _really this time_. Background: This has been proposed several times on this mailing list in the past. Most recent one was by Michael Platings in February this year [1], and there

> From: "Cohn, Robert S" <robert.s.cohn at intel.com> > > I am using R to multiply some large (30k x 30k double) matrices on a > 64 core machine (xeon phi). I added some timers to > src/main/array.c to see where the time is going. All of the time is > being spent in the matprod function, most of that time is spent in > dgemm. 15 seconds is in matprod in

Hi there fellow R-users, Im seeing some strange behaviour when I multiply a vector by a matrix Here is my script: > tr 1 2 3 4 5 6 0.2217903 0.1560525 0.1487908 0.1671354 0.1590643 0.1471667 > > ex1 a b c d e f 1 0.2309579 -3.279045 -0.6694697 -1.1024404 0.2303928 -1.5527404 2

Hi Ryan, In this case there already is an implementation for this, it's just hard to find being in the internals of the LoopVR pass. I'm planning to pull the multiply and udiv support out of there. Your patch looks good but beyond what Dan mentioned you have a bug calculating NewUpper: the constant ranges are half-open intervals where "[5, 10)" includes the value 9 but not

Nicolai, Can you do without the use of -fp-contract=fast (Options.AllowFPOpFusion == FPOpFusion::Fast ) and without Unsafe? As I SPIR-V’s usage of NoContraction flies in the face of both. If so, you should be able to get what you want, as then you are down to just IR flags. You will need a model to generate the correct behavior though in your SPIR-V implementation wrt IR flag emissions.

[just so i don't end up with "why haven't you spoken up"] On Sun, Sep 8, 2019 at 1:32 AM Philip Reames via llvm-dev <llvm-dev at lists.llvm.org> wrote: > > I do not support this. I feel the benefit is low, and the churn cost is high. > > I'm not strongly opposed or anything, I just don't believe this is worthwhile. Same thoughts. > Philip Roman

Hi Robert, thanks for the report and your suggestions how to make the NaN checks faster. Based on my experiments it seems that the "break" in the loop actually can have positive impact on performance even in the common case when we don't have NaNs. With gcc on linux (corei7), where isnan is inlined, the "break" version uses a conditional jump while the

What cost do you see here? Rui has done a significant amount of work to make this effectively zero cost. The improvements are meaningful, and (as was discussed on the other threads) pretty much every large scale change in the LLVM world has been shot down with objections like “it is too much churn”. This is a huge problem, because it leads to stagnation in the codebase and does not allow

-------- Original-Nachricht -------- Betreff: Re: [R] Adding and Multiplying two Unevaluated Expressions Datum: Tue, 01 Dec 2009 23:49:39 +0100 Von: Benjamin M?ller <ben_mueller.bm at web.de> An: Rolf Turner <r.turner at auckland.ac.nz> Referenzen: <20091201144125.316310 at gmx.net> <8E40E49F-E8FC-4FBD-8CC5-93789FFB0E53 at auckland.ac.nz> This works fine for your

Hi Jonas, > my target handles operands of multiplying instructions differently based on > signedness. since the result of a multiply doesn't depend on the signedness, I find it strange that your target differentiates between them. What I'm saying is that if you have (say) two i32 numbers a and b and you do a signed multiply: c = a *s b and an unsigned multiply d = a *u b