similar to: how can I get the coefficients of x^0, x^1, x^2, . , x^6 from expansion of (1+x+x^2)^3

Hi, I would like to get the coefficient of polynomial expansion. For example, (1+ x)^2 = 1 + 2x + x^2, and the coefficients are 1, 2 and 1. (1 + x + x^2)^3 = 1 + 3*x + 6*x^2 + 7*x^3 + 6*x^4 + 3*x^5 + x^6, and the coefficients are 1, 3, 6, 7, 6, 3, and 1. I know that we can use polynom library. Is there any other way to do it without loading a library. Thanks a lot for your help. Peter

Hi all, starting from a vector "v[1:n]" I would like to compute the coefficients of the polynomial (1+x^v[1])*(1+x^v[2])*...*(1+x^v[n]). The following code works but is extremely slow for a large "n" due to, I believe, the polynomial being factorized. I wanted to try the package "polynom" command "unclass" but I could not figure out how to input a

Hi, I am trying to write a package(A) for myself and need to use a function from another package(B) which is in R already(need to install it before use). Could anyone tell me how to implement that? Also I hope that my package gives an ERROR message(something like "STOP, please install package B first") if the package B is not installed yet. It is my first time to write a package. Thanks

Hi, I can not comprehend the linear fitting results of polynoms. For example, given the following data (representing y = x^2): > x <- 1:3 > y <- c(1, 4, 9) performing a linear fit > f <- lm(y ~ poly(x, 2)) gives weird coefficients: > coefficients(f) (Intercept) poly(x, 2)1 poly(x, 2)2 4.6666667 5.6568542 0.8164966 However the fitted() result makes sense: >

Hi guys, I am working on some code for automatically translating recursive functions into looping functions to implemented tail-recursion optimisations. See https://github.com/mailund/tailr As a toy-example, consider the factorial function factorial <- function(n, acc = 1) { if (n <= 1) acc else factorial(n - 1, acc * n) } I can automatically translate this into the loop-version

Interestingly, the <<- operator is also a lot faster than using a namespace explicitly, and only slightly slower than using <- with local variables, see below. But, surely, both must at some point insert values in a given environment ? either the local one, for <-, or an enclosing one, for <<- ? so I guess I am asking if there is a more low-level assignment operation I can get my

Following up on this attempt of implementing the tail-recursion optimisation ? now that I?ve finally had the chance to look at it again ? I find that non-local return implemented with callCC doesn?t actually incur much overhead once I do it more sensibly. I haven?t found a good way to handle parallel assignments that isn?t vastly slower than simply introducing extra variables, so I am going with

No clue, but see ?assign perhaps if you have not done so already. -- Bert Bert Gunter "The trouble with having an open mind is that people keep coming along and sticking things into it." -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) On Tue, Feb 27, 2018 at 6:51 AM, Thomas Mailund <thomas.mailund at gmail.com> wrote: > Interestingly, the

Good day everyone, I want to use the Gram-Charlier series expansion to model some data. To do that, I need functions to: 1) Calculate 'n' moments from given data 2) Transform 'n' moments to 'n' central moments, or 3) Transform 'n' moments to 'n' cumulants 4) Calculate a number of Hermite polynomials Are there R-functions to do any of the above?

> On Feb 11, 2018, at 7:48 AM, Thomas Mailund <thomas.mailund at gmail.com> wrote: > > Hi guys, > > I am working on some code for automatically translating recursive functions into looping functions to implemented tail-recursion optimisations. See https://github.com/mailund/tailr > > As a toy-example, consider the factorial function > > factorial <-

Hi everyone, I am a newbie to LLVM. I am trying to ban some of instructions in Mips Instruction, for example, lh, lhu, sh, and etc. I have tried to directly comment lh, lhu, and sh to make llvm not to choose these instruction when compiling, however, it usually cause a 'can not select ...' error when using 'short' data type in source code. Then I tried to expand these instructions

Thanks for your reply. We are trying to implement a simple Mips-based CPU with just for teaching purpose, so we delete some instructions which are not commonly used, thus the task won't be too hard for students. I am responsible for modifying the compiler so that the compiler won't emit unsupported instructions. In order to avoid "can not select" error, I am trying to expand

why do you want to "ban" certain instructions? is this for some architectural variant? the compiler is trying to match patterns from the target independent part of the code generator. if you remove instructions, the compiler in many cases will no longer be able to match certain patterns and you will get thos "can not select" messages. On 07/20/2012 03:05 AM, Geraint Yang

YOu have to look for which DAG fragments are not being matched. Then you can create patterns for those using alternate sequences. When you disablea given instruction, don't just disable it, but also look at what pattern it was matching. Then create a patten for that using remaining instructions or in some cases you might have to call a library function, as in the case of floating

Hi, I would like to know whether there exist algorithms to compute the coefficients or, at least, the degree of the minimal polynomial of a square matrix A (over the field of complex numbers)? I don't know whether this would require symbolic computation. If not, has any of the algorithms been implemented in R? Thanks very much, Ravi. P.S. Just for the sake of completeness, a

Hello, I am fairly new to using R and am trying to install it on my Linux machine, running Scientific Linux. I get through running 'configure' and 'make' OK, but when I run 'make check', I get the following error: make check make[1]: Entering directory `/home/gruchti/Programs/R-2.7.0/tests' make[2]: Entering directory `/home/gruchti/Programs/R-2.7.0/tests'

The derivative table resides in the function D. In S+ that table is extensible because it is written in the S language. R is faster but less flexible, since that table is programmed in C. It would be useful if R provided a mechanism for extending the derivative table, or barring that, provided a broader table. Currently unsupported mathematical functions of one argument include expm1, log1p,

SCEV expansion sometimes generates redundent expr even if there is an available expr which can be reused. The redundent exprs can be a lot different from existing exprs so that existing cleanup passes cannot remove them. https://llvm.org/bugs/show_bug.cgi?id=24920 https://llvm.org/bugs/show_bug.cgi?id=24442 https://reviews.llvm.org/D12090 and https://reviews.llvm.org/D21313 already relieved the

On Wed, Aug 24, 2016 at 3:07 PM, Daniel Berlin <dberlin at dberlin.org> wrote: > > > On Fri, Aug 19, 2016 at 3:57 PM, Wei Mi via llvm-dev > <llvm-dev at lists.llvm.org> wrote: >> >> SCEV expansion sometimes generates redundent expr even if there is an >> available expr which can be reused. The redundent exprs can be a lot >> different from existing

Merci beaucoup, Jean, for the bug report -- which I'm no "completeing" to R-bugs >>>>> "Jean" == Jean Coursol <coursol@cristal.math.u-psud.fr> >>>>> on Thu, 24 Jun 2004 15:22:37 +0200 (CEST) writes: Jean> I was exploring the polynom library with students: <and found a segmentation fault from parsing a long expression>