similar to: some questions about sympy (that is, rSymPy)

Hi all, I'm having major difficulty using the rSymPy package this week, but I have used it without problems before now. Here is an example of what's happening: > library(rSymPy) Loading required package: rJava > sympy("var('a b c d')") Error in .jcheck() : No running detected. Maybe .jinit() would help. And I have no idea how to fix it. I Have tried re-installing

Dear R People: I have been experimenting with rPython, rSymPy, and rJython. Here is my latest snag: > library(rJython) Loading required package: rJava Loading required package: rjson > library(rSymPy) > rJython <- rJython() > x <- "x" > y <- "y" > rJython$exec("from sympy import *") Error in .jcall("RJavaTools",

Dear R Users: I would like to use symbolic integration from rSymPy and pass in the actual function. So I have > sympy("x=Symbol('x')") and if I use > sympy("integrate(cos(x),x)") it works fine. But what I want to do is something like > y <- "cos(x)" > sympy("integrate(y,x)") "cos(x)*x" Has anyone run into this, please?

Dear R users, I have been using rsympy to solve a set of simultaneous equations from R. There are two solutions for the variable I'm interested in, xx[0] and xx[1], which are in terms of symbols called lam and conc. I'd like to pick out the one which is positive at (lam=0, conc=0) and call it mysol. In python I could write: if (xx[0].subs(lam,0)).subs(conc,0)>0: mysol=xx[0]

Hey, what is the R function for the mathematical limit ? e.g. to calculate and return the amount that the expression X^2 +X +2 approach as X approach 2 (X-> 2) thanks hassan [[alternative HTML version deleted]]

I am working on a project that requires me to do very large factorial evaluations. On R the built in factorial function and the one I created both are not able to do factorials over 170. The first gives an error and mine return Inf. Is there a way to have R do these larger calculations (the calculator in accessories can do 10000 factorial and Maple can do even larger) -- View this message in

Hi, as I find problems with yacas package... is there any R function equivalent to the yacas function "Factor" ? the factor function which i found in the R help is not the same. it doesn't factor an algebraic expression...... thanks hassan [[alternative HTML version deleted]]

Hi, can anyone tell me if R can be used to rearrange very complicated equations in terms of one of the variables? I have: dx/dt = a*b*m*y*(1-x)-r*x and, having set: dy/dx = 0, need to rearrange in terms of x. The problem I have is that I don't know how to rearrange equations when the variables are not yet defined (I get messages warning me that x etc can't be found). I'm not sure

Hi, I'm wondering if someone has solved the problem of converting very large integers to hex. I know about format.hexmode and as.hexmode, but these rely on integers. The numbers I'm working with are overflowing and losing precision. Here's an example: x <- "6595137340052185552" # stored as character as.integer(x) # warning about inaccurate conversion

Hi I recently gave a presentation about Automatic Differentiation (AD) and R at the Eighth Euro AD Workshop in Oxford (17/07/09). The presentation was intended as a general introduction to R and the desire for a generic AD interface for R. During the presentation I emphasised the need and the high level of interest that the R community has in developing such an interface and that input from the

Las dos Enviado desde mi iPhone > El 28/11/2013, a las 18:07, "Carlos J. Gil Bellosta " <cgb en datanalytics.com> escribió: > > ¿Numérica o simbólicamente? > > Un saludo, > > Carlos J. Gil Bellosta > http://www.datanalytics.com > > El día 28 de noviembre de 2013 18:03, jmcontreras <jmcontreras en ugr.es> escribió: >> Hola a todos

Martin (see below) gives a good explanation of the difference between AD and symbolic differentiations. I'm of the opinion we can use both. However, the real issue as far as I'm concerned (from an optimizer's point of view, which may also be that of ODE and PDE folk) is that right now none of the offerings that we have are easy to use. Indeed, usability is one of the key issues in my

In efforts to improve optimization tools for R, one of my interests has been getting automatic differentiation capabilities so that analytic rather than numerical derivatives can be used. They would be helpful in several other areas besides optimization, My timings show factors of the order of 1000s in time improvements by avoiding numerical derivatives in some cases. There has been some work in

Hi again. I'm putting together a little project with R, python, and a website. So I have an HTML file, a py file, an R file. Here is the HTML file: <form action="/cgi-bin/radio4.py" method="post" target="_blank"> <input type="radio" name="subject" value="Integrate" /> Integrate <input type="radio"

I rewrote scatter.smooth to handle missing values, but I have a question about a move I had to make. Here's the code: Mscatter.smooth<-function (x, y, span = 2/3, degree = 1, family = c("symmetric", "gaussian"), xlab = deparse(substitute(x)), ylab = deparse(substitute(y)), ylim = range(y, prediction$y), evaluation = 50, ...) { if (inherits(x,

Hello Aaron, Anton, LLVM-dev, While working on http://llvm.org/PR13676#c6 I found out that whenever I compile code with class methods returning structures it get generated incompatible with MSVC. Looking at lib/Target/X86/X86CallingConv.td, I found out that CC_X86_32_ThisCall maps SRet to EAX but in fact it should push the address of the return temp on stack. The following patch fixes the issue

On Tue, Dec 10, 2013 at 5:08 PM, Hans Wennborg <hans at chromium.org> wrote: > On Tue, Dec 10, 2013 at 4:39 PM, Reid Kleckner <rnk at google.com> wrote: >> I think we need to relax the test cases. MSVC usually prints the calling >> convention, and it's often useful information. > > I was going to argue that MSVC doesn't print them, but then I tried, >

I think we need to relax the test cases. MSVC usually prints the calling convention, and it's often useful information. Maybe we can make the diagnostic text smaller by using the __thiscall, __cdecl, __stdcall, etc keywords when printing types with LangOpts.MicrosoftExt, but it will require moving the attribute from after the identifier to before, which is exciting. On Tue, Dec 10, 2013 at

On Tue, Dec 10, 2013 at 4:39 PM, Reid Kleckner <rnk at google.com> wrote: > I think we need to relax the test cases. MSVC usually prints the calling > convention, and it's often useful information. I was going to argue that MSVC doesn't print them, but then I tried, and you're right - it does :) I'll start relaxing the tests then. > Maybe we can make the

Hello everyone, I encountered a strange behaviour which I can't explain. I'm developing an application under Windows 7 64bit. This application is using the LLVM library to load and resolve BC files generated with clang. Then the program picks some functions from the module and executes them. That's the theory - but now it's getting strange. The BC files are compiled for 64bit