similar to: Distance between lines

Hello All, This is my third time attempting to post this message. I don't see it in the archive, so I'm guessing it is not getting through. If I am wrong, my apologies. I am trying to do a GLS regression, (X'V^-1X)^-1X'V^-1y, using the gls() function from the nlme package. I have the covariance matrix V. I have been searching for a way to specify the correlation structure

Dear R-Help community, I am trying to overlay a single contour line over a correlation plot using levelplot in the lattice package. These are the two arrays: 1) a correlation plot over Africa - so each grid square is a different colour dependent on correlation - this is in an array: result_cor with dim[465,465] 2) a single contour line from a ***different data source*** - this is from data

I have a list of polygons generated by the contourLines() command (each object of the list is a list in itself with two objects: a vector of x values, and a vector of y values for each vertex). I wish to convert that list into a gpc.poly object of multiple contours. How do I do this? gpclib apparently has no method of coercing lists into the gpc.poly object type. As well, when I have a

Requisite info: R version 2.11.1 (2010-05-31) running on a 64 bit HP Windows 7 machine. Greetings, R-ians: I have used contour() for several years. Now I would like to extract from a contour plot the x, y coordinates of a contour z=constant. This seems as though it would be straight-forward but I''ve been unsuccessful in my searches of CRAN. Can anyone provide a hint?

Hello All, Is there a fast way to find the index(row and column) of a point in a matrix? Thanks, John. -- -------------------------------------------------------------------------- Dr. John Janmaat Department of Economics, Acadia University, Wolfville, NS, B4P 2R6 E-mail: jjanmaat at acadiau.ca Web: http://ace.acadiau.ca/~jjanmaat Tel: 902-585-1461 Fax: 902-585-1070

Hello, I have a system of quadratic equations (results of a Hamiltonian optimization) which I need to find the roots for. Is there a package and/or function which will find the roots for a quadratic system? Note that I am not opimizing, but rather solving the first order conditions which come from a Hamiltonian. I am basically looking for something in R that will do the same thing as fsolve in

Hello, I'm playing around with cluster analysis, and am looking for methods to select the number of clusters. I am aware of methods based on a 'pseudo F' or a 'pseudo T^2'. Are there packages in R that will generate these statistics, and/or other statistics to aid in cluster number selection? Thanks, John. --

Hello All, I am drawing four contour plots on a 2x2 layout. I need to downsize the contour line labels. cex and labcex do not seem to work. Any suggestions? Thanks, John. -- -------------------------------------------------------------------------- Dr. John Janmaat Department of Economics, Acadia University, Wolfville, NS, B4P 2R6 E-mail: jjanmaat at acadiau.ca Web:

Do you know what steps I need to take to add a scale to a plot? I'm pulling my example out of "An Introduction to R: Software for StatisticalModelling & Computing" (see the R code around Figure 76). I would like to add a scale to the image produced by the following code.? I would like to the scale to list the distance?and units:? data(volcano) x <- 10*(1:nrow(volcano)) y

Hello, Is there a package that implements the Cochrane-Orcutt itterative procedure for dealing with autocorrelation in a regression model? Thanks, John. -- ========================================== John Janmaat Department of Economics Acadia University, Wolfville, NS, B0P 1X0 (902)585-1461 All opinions stated are personal, unless otherwise indicated.

Hello All, Is there an analogue to \underbar or the AMS math \underline in graphical math expressions? Thanks, John. -- ===================================================================================== Dr. John Janmaat Department of Economics Acadia University Wolfville, Nova Scotia, Canada B4P 2R6 TEL: 902-585-1461 WWW: http://ace.acadiau.ca/~jjanmaat/ EMAIL: jjanmaat at acadiau.ca June

Hello All, I'm looking to test a variable in a logit model (glm(..., binomial(link="logit"))) for exogeneity (endogeneity). At this point I am planning to try implementing Jeffery Grogger's "A Simple Test for Exogeneity in Probit, Logit, and Poisson Regression Models", Economic Letters, 1990. To do this, I need to be able to do an instrumental variables NLS

Hi all, I wonder why there is so little software for carpet plots (german: Rasterdiagramm) (Three dimensional plot (x, y, z), the 3rd dimension (z) symbolized by colourgradients). Besides from one or the other non free software I only found an OpenOffice macro, a combination of Gnuplot and Excel (an Excel macro calling gnuplot) (http://www.johannes-hopf.de/2009/12/carpet-plot-version-1-3/9 and

Hello, I am trying to get a time derivative on a plot title. I prefer to have it in the form \dot{s_i}, but \partial s_i/\partial t would be O.K. In the graphics demo I cannot find either a dot or a partial equivalent. Thanks, John. -- ========================================== John Janmaat Department of Economics Acadia University, Wolfville, NS, B0P 1X0 (902)585-1461 All opinions stated

I am working on plotting a response surface using wireframe(). The default style/orientation is z | | y | \ | \ | \ | \ | \ | \ | \ | \|________________x 0 Now what I want the orientation of axes is: z | | | |

Hello, I need to solve a non-linear optimization with non-linear constraints. The 'nlm' routine does not seem to allow constraints. Is there a package for solving such problems in R? Thanks, John. -- ========================================== John Janmaat Department of Economics Acadia University, Wolfville, NS, B0P 1X0 (902)585-1461 All opinions stated are personal, unless

Hello, I have a linear model with different slopes for different treatment groups. I need to pairwise compare the different slope estimates for the different treatment groups. Is there a package that does pairwise comparisons of slope coefficients, making the appropriate adjustments in the P values? Thanks, John. -- ========================================== John Janmaat Department of

Hello, I am looking for a routine to do a logistic regression. In the book "Modern Applied Statistics with S-PLUS" a function is described which uses the 'ms' command. Is there an analogue for R, or an alternative approach that can accomplish the same thing? Thanks, John. -- ========================================== John Janmaat Department of Economics Acadia

I want to use contourLines() to get contour line coordinate vectors, but I don't want to make a plot. However contourLines() insists on opening a graphics device. Is there a way tell it not to do this? > version platform i686-pc-linux-gnu arch i686 os linux-gnu system i686, linux-gnu status Patched major 2 minor 1.0 year 2005 month 04 day 20 language R

Hi Folks, I have been using contour() to produce some contour plots (of a spatially-smooted density produced by kde2d()), with very satisfactory results. I now want access to the coordinates of the points on the contours, and it would seem that contour() does not return a value, so there is nothing from which these could be extracted. However, apparently contourLines() does, and it seems to be