Helical symmetry

Symmetrizing a particle

Helical operator syntax

Symmetrizing a helical particle can be done with the usual tool dsym:

 vh = dsym(v,<operator>);

where operator represents any symmetry operator. The syntax for helical operators is:

 h [<phi>,<dz>,<repetitions[optional]>,<rotational symmetry[optional]>]}} 

Here:

• phi is the angular increment in degrees
• dz is the axial rise in pixels
• the number of repetitions
• additional Cn rotation to account for n-start helices

Using symmetrization in alignment projects

The simplest way is to input one operator with the syntax described #Helical operator syntax above in the Numerical settings area of the dcm GUI.

This allows to impose a given symmetrization. In order to estimate the symmetry, you will need to create a plugin.