projtree

Generates a list of projections used for high speed particle classification

projtree <infile> <outfile> [level=2,3] [sym=<cn,icos,etc]

Parameters:


<infile>Projection file
<outfile>Output 'tree' text file
[level=2,3]The decomposition level to use
[sym=<cn,icos,etc]Model symmetry, used for azimuth wrapping

Usage:

projtree proj.img proj.tree level=2 sym=c4

Description

This program is used internally by refine. It generates a file used by classesbymra. Normally classesbymra comapres each particle to each projection. The 'tree' option allows each particle to be compared to 1/4 (level 2) or 1/9 (level 3) of the projections initially. Each particle is then locally refined to determine the exact matching projection. So, the total number of comparisons is N/4 + 6 or N/9 + 18. This is an improvement only if the number of projections is sufficiently large. There is also a potential problem if the images are very noisy and the 'best' peaks are sharp and poorly defined. If the incorrect initial maxima is chosen, the 'detailed' maxima will also obviously be wrong.


EMAN Manual page, generated Tue Oct 8 21:38:48 2002