EMBL Virus Structure Resource

Emicobg


Description

This program combines the sampled data to generate the Gn 's for a selected subset of the particles. The output is a file EMICOBG.DAT which contains the combined data for the set.

Program prints the mean residual for each Z level and flags components which have no values.

See the warnings about recycling below.

For combining images with different regions of resolution (for example when combining images of different defocus) use ranges of annuli for the different regions.

Inputs

Sample runs


com file for complete reconstruction
annotated com file for complete reconstruction
corresponding log file

Update History

Current version - 26jul95

eigenvalue limit, the program recycles to a lower number of parameters. In practice this means that some of the coefficients of the BG expansion will not be calculated. Since the BG expansion is over cylindrical rather than icosahedral coordinates, the resulting map will NOT have exact icosahedral symmetry and, in extreme cases, will resemble a badly distorted bowler hat. This can be corrected by symmetrizing the result so that starting bowler hat density now looks like an icosahedrally arranged bowler hat chimera. This does not increase the biological significance of the result. Recycling is not a bug but a warning that you should be less optimistic about your ability to extract silk purses from sow's ears or 2A structures from 50A data.

Naturally when you are attempting a single particle reconstruction you will always get this error and you will always ignore it and you will NEVER completely believe the result and are honor bound not to try to publish it!!!!

character overflows output format 26jul95 sdf
For very large data sets the number of parameters solved exceeds 1000 and so the number can no longer be written in the nice compact form usually used for the output (i3 per entry). This gives an error but execution continues and there is NO effect on the reconstructed density.

The proper response is not to worry but rather give thanks that you have so much data...


| EMBL Home Page | Search EMBL | Mail to EMBL Webmaster
Author: Stephen Fuller
=======================> Return to Top Virus Page
Last Updated: 30 July, 1995