search for: tpcolson

...ems to consider a very large dataset, a 12MB text file of lat,long,and height values, 130,000 rows to be exact. Here's what I get: Thomas Colson North Carolina State University Department of Forestry and Environmental Resources (919) 673 8023 tom_colson at ncsu.edu Calendar: www4.ncsu.edu/~tpcolson

...n't seem to figure out how to "attach" a new column (or make a new dataset) that has a colums of ranks, or how to calculate the rank. Thanks for any help. Thomas Colson North Carolina State University Department of Forestry and Environmental Resources (919)624-6329 (919)515 3434 tpcolson at ncsu.edu Schedule: www4.ncsu.edu/~tpcolson

...hpc/Hardware/Hardware.php) a wasted effort? We have the memory and drive space to do this. Thanks for any advice Tom Colson Center for Earth Observation North Carolina State University Raleigh, NC 27695 (919) 515 3434 (919) 673 8023 tom_colson at ncsu.edu Online Calendar: http://www4.ncsu.edu/~tpcolson

Dear R users, I'm trying to write a small function in order to compute empirical cumulative density function.All seems to work but when I try to plot the function, I always get error messages. This is the function I use mecdf<-function(u,v,z) { u=sort(u) v=sort(v) n=length(u) nb=0 for (i in seq(1,n)) { if (u[i]<z & v[i]<z) { nb<-nb+1 } } nb=nb/n

I'm trying to calculate a cumulative area distribution (graph) of drainage areas. This is defined as P(A > A*). Simple in principle. I can do this in excel, with "COUNTIF", which will count the number of cells in the row "area" that have area A, then determine, for each cell in the row "area, how many cells exceede that area, then dividing that number by the total

I'm not sure I'm barking up the right tree here, but would I need to make use of groups to plot two separate datasets within ONE panel in xyplot? The desired end result is a single xy plot of two separate (but similar in values and ranges). Full code follows, xyplot code at bottom #########Determine Frequencies ##########coastal_slope #needs the maptools package to read ESRI grid