Actually not only doing what is classically called "nucleation", but creating new high angle grain boundaries (HAGBs) from misorientations in flynns.  
  
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# INFO: These codes have hardly been changed by Florian Steinbach (therefore no FS_ prefix). The main changes are:
#
#    1. Possibility to exclude a phase (i.e. air)
#    2. Tracking of polygonisation events
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# The codes are by Albert Griera, contact him for more information
#  * Institution: Departament Geologia, Universitat Autònoma de Barcelona
#  * Email: albert.griera@uab.cat
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Usage:

Two Elle modules are necessary: 
1) subgrain_unodes_alb
2) u2f_sgb_alb (u2f = unode2flynn)

The 1st is searching for clusters of unodes (in existing flynns) within a certain misorientation angle. The 2nd module creates a new flynn around these clusters. As a third stage, you should always run a topology check afterwards (FS_topocheck).

# # # # # Usage of subgrain_unodes_alb: # # # # #

    subgrain_unodes_alb -i file.elle -u A B C D -n

    A: gridsize (default is 256)
    B: high angle grain boundary (threshold for subgrains, default 5°)
    C: Excluded phase (any phase ID you want to exclude from subgrain creation and nucleation, default is 2, set to 0 to switch this off)
    D: Neighbour order, default = 1 means 1st order neighbours = 8 neighbours

# # # # # Usage of u2f_sgb_alb: # # # # #

    subgrain_unodes_alb -i file.elle -u A B C D -n

    A: gridsize (default is 256)
    B: cluster size (min. number of unodes in a cluster to create new flynn, default: 10)
    C: Set to 1 to only use the flynn id indicated in D (but usually KEEP AT 0, default: 0)
    D: See C :-)



IMPORTANT: Keep the symmetry.symm file in the folder form where you call the codes.
