search for: ranns

Hi, I'm trying to implement the DBSCAN algorithm to get O(N*LogN) complexity and I'd need a spatial tree of some sort (kd,r,bd..), or a function that computes radius-based search on spatial data, i.e. given a radius eps finds ALL the points which fall in the corresponding hypersphere centered on the current examined point. Is there a package with this features? So far I found RANN

...re may be a faster and more elegant way to do this in R. In Python (Numeric) the same can be achieved with ix=Numeric.searchsorted(X[1:-1],Xi), which is quite compact. So, does anyone know of a corresponding R call that can achive the same? Sincerely, Halldór -- Halldór Björnsson Deildarstj. Ranns. & Þróun Veðursvið Veðurstofu Íslands Halldór Bjornsson Weatherservice R & D Icelandic Met. Office [[alternative HTML version deleted]]

I am looking for an efficient way to find near neighbors... More specifically... I have two sets of points: A & B and I want to find points in set B which are closer to set A than some cutoff (or n-closest) I will appreciate very much any pointers... Ryszard -------------------------------------------------------------------------- Confidentiality Notice: This message is private and may

Hi I have a table with ID (1 to 183) and Location (144 to -22). My problem is that I want to select the 10 ID's that are closest in Location to ID 1, ID 2 and so on. Also, some ID have the same Location. Say, if 11 ID's are closest to ID 100 I want to randomly choose one of the ID's to select 10 ID's total. Thank you -- View this message in context:

The following runs in an eyeblink on my 700Mhz Thinkpad T-20 (256 MB RAM) with Windows NT: var(matrix(rnorm(4000000),ncol=4,nrow=1000000)) This also has the virtue of being quite readable. You could allow an arbitrary covariance matrix and mean vector and it increases the time slightly, but still only about 5 seconds. Regarding performance, having tons of RAM is crucial. My Windows NT and the

Dear All, The institute I work for is organizing an internal workshop for High Performance Computing (HPC). I am planning to attend it and talk a bit about fluid dynamics, but there is also quite a lot of interest devoted to data post-processing and management of huge data sets. A lot of people are interested in image processing/pattern recognition and statistic applied to geography/ecology, but I

I have successfully encoded a wav file in android using speex(ndk). But when i try to decode it back, the file size keep on increasing to a very large size. The recorded audio file consists of sample rate - 8000 , 16 BIT, MONO. Why the decoder gives such a large size wav file? -------------- next part -------------- An HTML attachment was scrubbed... URL: