[R] Quantreg - 'could not find functionrq'

2010-01-07 Thread Gough Lauren
Hi all, I'm having some troubles with the Quantreg package. I am using R version 2.10.0, and have downloaded the most recent version of Quantreg (4.44) and SparseM (0.83 - required package). However, when I try to run an analysis (e.g. fit1-rq(y~x, tau=0.5)) I get an error message saying

[R] Dividing a pixel image into factors - (cut.im(), cut.default())

2009-12-04 Thread Gough Lauren
Hi, I have a numeric pixel image which I would like to divide into factors for analysis in Spatstat. I have found that I can use cut.im() function to divide the range of pixel values into a series of equal length intervals (e.g. if my pixels values range from 0 to 60, cut.im(X.im,breaks=2)

[R] Fitting power laws to size distribution data

2009-07-10 Thread Gough Lauren
Hi, I have several datasets recording the size of individuals shrubs. I would like to test various distribution functions to see which fits my data most closely. So far I have used the fitdistr tool in the MASS package to get the parameter estimates for the best-fit lognormal, exponential and

[R] Spatstat - K2 index

2008-12-01 Thread Gough Lauren
Hi all, I'm using spatstat to investigate the spatial structure of an arid shrub population. The first-order intensity of my data does not appear to be homogenous, so I would like to use inhomogeneous techniques. I realise there is a inhomogeneous K-function available in spatstat, but there

Re: [R] Spatstat help - quadratcount query

2008-10-23 Thread Gough Lauren
2008 05:34 To: R-help Forum Cc: Gough Lauren; Rolf Turner Subject: Re: [R] Spatstat help - quadratcount query Gough, Lauren wrote: I am using quadratcount in spatstat to divide a window containing a point pattern into a grid of quadrats containing the intensity of points in each quadrat

[R] Spatstat help - quadratcount query

2008-10-22 Thread Gough Lauren
Hi all, I am using quadratcount in spatstat to divide a window containing a point pattern into a grid of quadrats containing the intensity of points in each quadrat. My data is in UTM co-ordinates. My window is defined as follows:

[R] Fitting weibull, exponential and lognormal distributions to left-truncated data.

2008-10-07 Thread Gough Lauren
Dear All, I have two questions regarding distribution fitting. I have several datasets, all left-truncated at x=1, that I am attempting to fit distributions to (lognormal, weibull and exponential). I had been using fitdistr in the MASS package as follows: fitdistr-(x,weibull) However, this

[R] Graphics winder keeps disappearing!

2008-09-25 Thread Gough Lauren
Dear all, I am a very new user to R (for windows) (since Monday!) so please excuse me if I am asking an obvious question! I am experiencing some problems with the graphics window - in short, it keeps disappearing. i.e. I can type x-c(1,3,6,4,9) plot(x) No errors are produced, but not