search for: mathomat

I am trying to write a function that will solve a simple system of nonlinear equations for the parameters that describe the beta distribution (a,b) given the mean and variance. mean = a/(a+b) variance = (a*b)/(((a+b)^2) * (a+b+1)) Any help as to where to start would be welcome. -- Scott Story Graduate Student MSU Ecology Department 319 Lewis Hall Bozeman, Mt 59717 406.994.2670 sstory at

Hi Folks, I am using Windows 2000 and was wondering what (Open Source) software R users use or might recommend for symbolic computations (aside from the ol' noggin, e.g., Maxima, Mathomatic) . Thanks, Hank Dr. Martin Henry H. Stevens, Assistant Professor 338 Pearson Hall Botany Department Miami University Oxford, OH 45056 Office: (513) 529-4206 Lab: (513) 529-4262 FAX: (513) 529-4243 http://www.cas.muohio.edu/botany/bot/henry.html http://www.muohio.edu/ecology

Thanks to Gabor, Duncan, and Peter. I knew the answer had something to do with solving for a and b in terms of mean and variance. I will build a function using the equations you provided Duncan and will look into using Mathomatic in the future Gabor. Appreciate the help. Peter, this was not homework but I understand your concern. I don't use listserves that often but they do open a whole arena for students to get free information (hadn't even crossed my mind). Just as an aside, I take it that R cannot solve no...

...following questions: (i) does R have any native computer algebra functionality that would allow > expression(250000*L) + expression(250000*M) to evaluate to [1] expression(250000*(L+M)) (ii) if not, does anyone have experience with integrating available computer algebra platforms (such as Mathomatic, which Gabor discussed in an earlier thread, but maybe not Mathomatic, because of its lack of natural log support) with R, i.e, passing expressions out for algebraic computations and then returning the result? are there any packages available to provide APIs to any systems? Any open source syst...

...bugsx, clustalw, fastdnaml, fastlink, garlic, gromacs, hmmer, loki, mipe, molphy, muscle, ncbi, phylip, rasmol, readseq, seaview, t-coffee, textopo, and more; - continued strong mathematics / computational algrebra support: axiom, blacs, calc, euler, gap, giac, mathomatic, maxima, pari, scalapack, scilab, texmacs, yacas, yorick; - strong visualization / graphics support: dx, garlic, gdpc, gnuplot, grace, grass, gri, illuminator, kst, labplot, mayavi, matplot, proj, plplot, plotmtv, rasmol, starplot, vtk, xd3d, xgraph, ygraph;...

...bugsx, clustalw, fastdnaml, fastlink, garlic, gromacs, hmmer, loki, mipe, molphy, muscle, ncbi, phylip, rasmol, readseq, seaview, t-coffee, textopo, and more; - continued strong mathematics / computational algrebra support: axiom, blacs, calc, euler, gap, giac, mathomatic, maxima, pari, scalapack, scilab, texmacs, yacas, yorick; - strong visualization / graphics support: dx, garlic, gdpc, gnuplot, grace, grass, gri, illuminator, kst, labplot, mayavi, matplot, proj, plplot, plotmtv, rasmol, starplot, vtk, xd3d, xgraph, ygraph;...

...ugsx, clustalw, fastdnaml, fastlink, garlic, gromacs, hmmer, loki, mipe, molphy, muscle, ncbi, phylip, rasmol, readseq, seaview, t-coffee, textopo, ImageJ, and more; - continued strong mathematics / computational algrebra support: axiom, blacs, calc, euler, gap, giac, mathomatic, maxima, pari, scalapack, scilab, texmacs, yacas, yorick; - continued strong visualization / graphics support: dx, garlic, gdpc, gnuplot, grace, grass, gri, illuminator, kst, labplot, mayavi, matplot, proj, plplot, plotmtv, rasmol, starplot, vtk, xd3d, xgraph,...

...ugsx, clustalw, fastdnaml, fastlink, garlic, gromacs, hmmer, loki, mipe, molphy, muscle, ncbi, phylip, rasmol, readseq, seaview, t-coffee, textopo, ImageJ, and more; - continued strong mathematics / computational algrebra support: axiom, blacs, calc, euler, gap, giac, mathomatic, maxima, pari, scalapack, scilab, texmacs, yacas, yorick; - continued strong visualization / graphics support: dx, garlic, gdpc, gnuplot, grace, grass, gri, illuminator, kst, labplot, mayavi, matplot, proj, plplot, plotmtv, rasmol, starplot, vtk, xd3d, xgraph,...