[R] Python difflib R equivalent?

2011-07-28 Thread Paul
Hi, Does anyone know of a R library that is equivalent in functionality to the Python standard libraries' difflib library? The python docs say this about difflib: This module provides classes and functions for comparing sequences. It can be used for example, for comparing files, and can produce

Re: [R] Python difflib R equivalent?

2011-07-28 Thread Bert Gunter
Paul: 1. I do not know if any such library exists. 2. However, if I understand correctly, one usually does this sort of thing in R with functions like ?match (or ?%in%) and logical comparison operations like ?== . Of course, for numeric comparisons, you need to be aware of R FAQ 7.31 If you

Re: [R] Python difflib R equivalent? -- Correction

2011-07-28 Thread Bert Gunter
Item 1 below should be changed to: 1. I do not know if any such PACKAGE exists. (A library in R is a file directory where R packages are stored) -- Bert On Thu, Jul 28, 2011 at 8:05 AM, Bert Gunter bgun...@gene.com wrote: Paul: 1. I do not know if any such library exists. 2. However, if

Re: [R] Python difflib R equivalent?

2011-07-28 Thread Prof Brian Ripley
On Thu, 28 Jul 2011, Bert Gunter wrote: Paul: 1. I do not know if any such library exists. Not to my knowledge, and we have contemplated providing such functions. But for files see e.g. tools::Rdiff, and generally R will not be a good way to do this sort of thing on files (since the

Re: [R] Python difflib R equivalent?

2011-07-28 Thread Spencer Graves
There is a package rJython, which claims to provide an R interface to Python via Jython. I haven't used it, but the lead author, Gabor Grothendieck, is well known in the R community. Spencer On 7/28/2011 9:15 AM, Prof Brian Ripley wrote: On Thu, 28 Jul 2011, Bert Gunter wrote: Paul: 1

Re: [R] Python and R

2009-02-21 Thread Douglas Bates
Different methods of performing least squares calculations in R are discussed in @Article{Rnews:Bates:2004, author = {Douglas Bates}, title= {Least Squares Calculations in {R}}, journal = {R News}, year = 2004, volume = 4, number = 1, pages

Re: [R] Python and R

2009-02-20 Thread Kenn Konstabel
Decyphering formulas seems to be the most time consuming part of lm: mylm1 - function(formula, data) { # not perfect but works F - model.frame(formula,data) y - model.response(F) mt - attr(F, terms) x - model.matrix(mt,F) coefs - solve(crossprod(x), crossprod(x,y))

Re: [R] Python and R

2009-02-20 Thread Gabor Grothendieck
Note that using solve can be numerically unstable for certain problems. On Fri, Feb 20, 2009 at 6:50 AM, Kenn Konstabel lebats...@gmail.com wrote: Decyphering formulas seems to be the most time consuming part of lm: mylm1 - function(formula, data) { # not perfect but works F -

Re: [R] Python and R

2009-02-19 Thread Esmail Bonakdarian
Doran, Harold wrote: lm(y ~ x-1) solve(crossprod(x), t(x))%*%y# probably this can be done more efficiently You could do crossprod(x,y) instead of t(x))%*%y that certainly looks more readable (and less error prone) to an R newbie like myself :-)

Re: [R] Python and R

2009-02-19 Thread Esmail Bonakdarian
Hi Kenn, Thanks for the suggestions, I'll have to see if I can figure out how to convert the relatively simple call to lm with an equation and the data file to the functions you mention (or if that's even feasible). Not an expert in statistics myself, I am mostly concentrating on the

Re: [R] Python and R

2009-02-19 Thread Esmail Bonakdarian
Gabor Grothendieck wrote: On Wed, Feb 18, 2009 at 7:27 AM, Esmail Bonakdarian esmail...@gmail.com wrote: Gabor Grothendieck wrote: See ?Rprof for profiling your R code. If lm is the culprit, rewriting your lm calls using lm.fit might help. Yes, based on my informal benchmarking, lm is the

Re: [R] Python and R

2009-02-19 Thread Gabor Grothendieck
On Thu, Feb 19, 2009 at 8:30 AM, Esmail Bonakdarian esmail...@gmail.com wrote: Hi Kenn, Thanks for the suggestions, I'll have to see if I can figure out how to convert the relatively simple call to lm with an equation and the data file to the functions you mention (or if that's even

Re: [R] Python and R

2009-02-18 Thread Gabor Grothendieck
On Tue, Feb 17, 2009 at 6:59 PM, Esmail Bonakdarian esmail...@gmail.com wrote: Well, I have a program written in R which already takes quite a while to run. I was just wondering if I were to rewrite most of the logic in Python - the main thing I use in R are its regression facilities - if it

Re: [R] Python and R

2009-02-18 Thread Barry Rowlingson
2009/2/17 Esmail Bonakdarian esmail...@gmail.com: Well, I have a program written in R which already takes quite a while to run. I was just wondering if I were to rewrite most of the logic in Python - the main thing I use in R are its regression facilities - if it would speed things up. I

Re: [R] Python and R

2009-02-18 Thread Esmail Bonakdarian
Gabor Grothendieck wrote: See ?Rprof for profiling your R code. If lm is the culprit, rewriting your lm calls using lm.fit might help. Yes, based on my informal benchmarking, lm is the main bottleneck, the rest of the code consists mostly of vector manipulations and control structures. I

Re: [R] Python and R

2009-02-18 Thread Gabor Grothendieck
On Wed, Feb 18, 2009 at 7:27 AM, Esmail Bonakdarian esmail...@gmail.com wrote: Gabor Grothendieck wrote: See ?Rprof for profiling your R code. If lm is the culprit, rewriting your lm calls using lm.fit might help. Yes, based on my informal benchmarking, lm is the main bottleneck, the rest

Re: [R] Python and R

2009-02-18 Thread Kenn Konstabel
lm does lots of computations, some of which you may never need. If speed really matters, you might want to compute only those things you will really use. If you only need coefficients, then using %*%, solve and crossprod will be remarkably faster than lm # repeating someone else's example #

Re: [R] Python and R

2009-02-18 Thread Doran, Harold
lm(y ~ x-1) solve(crossprod(x), t(x))%*%y# probably this can be done more efficiently You could do crossprod(x,y) instead of t(x))%*%y __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting

[R] Python and R

2009-02-17 Thread Esmail Bonakdarian
Hello all, I am just wondering if any of you are doing most of your scripting with Python instead of R's programming language and then calling the relevant R functions as needed? And if so, what is your experience with this and what sort of software/library do you use in combination with

Re: [R] Python and R

2009-02-17 Thread Warren Young
Esmail Bonakdarian wrote: I am just wondering if any of you are doing most of your scripting with Python instead of R's programming language and then calling the relevant R functions as needed? No, but if I wanted to do such a thing, I'd look at Sage: http://sagemath.org/ It'll give you

Re: [R] Python and R

2009-02-17 Thread Barry Rowlingson
the two together, it's easiest with 'rpy'. This lets you call R functions from python, so you can do: from rpy import r r.hist(z) to get a histogram of the values in a python list 'z'. There are some complications converting structured data types between the two but they can be overcome

Re: [R] Python and R

2009-02-17 Thread Esmail Bonakdarian
Hello! On Tue, Feb 17, 2009 at 5:58 PM, Warren Young war...@etr-usa.com wrote: Esmail Bonakdarian wrote: I am just wondering if any of you are doing most of your scripting with Python instead of R's programming language and then calling the relevant R functions as needed? No, but if I

Re: [R] Python and R

2009-02-17 Thread Esmail Bonakdarian
On Tue, Feb 17, 2009 at 6:05 PM, Barry Rowlingson b.rowling...@lancaster.ac.uk wrote: 2009/2/17 Esmail Bonakdarian esmail...@gmail.com: When I need to use the two together, it's easiest with 'rpy'. This lets you call R functions from python, so you can do: from rpy import r r.hist(z