Export trajectory frames#

This example demonstrates how to export structures for each frame along a trajectory (SBPath).
def export_trajectory(path, file_basename, file_format):
    '''
    Exports trajectories from an SBPath node 'path'
    to files with a name starting with 'file_basename' and extension 'file_format'
    '''
    # set the current step for the Path to 0
    path.currentStep = 0
    trajectory_files = []

    # get a node indexer for all structural models
    indexer = SAMSON.getNodes('n.t sm')

    if len(indexer):
        # loop over steps in the Path
        for step in range(path.numberOfSteps):

            # increment the current step
            path.currentStep = step

            # a name of a file
            fn = file_basename + str(step) + '.' + file_format

            # export current trajectory into a file 'fn' with default parameters ([])
            if SAMSON.exportToFile(indexer, fn, []):
                # append list of trajectory files
                trajectory_files.append(fn)

    # return list of trajectory files
    return trajectory_files

def export_to_PDB(path, file_basename):
    '''
    Export trajectory from path into PDB format
    '''
    return export_trajectory(path, file_basename, 'pdb')

def export_to_XYZ(path, filename):
    '''
    Export trajectory from path into XYZ format
    '''
    return export_trajectory(path, file_basename, 'xyz')


# get an indexer with all paths in the active document
path_indexer = SAMSON.getNodes('node.type path')

if len(path_indexer):
    # take the first path
    path = path_indexer[0]
    # export the path to a pdb file
    export_to_PDB(path, "/path/to/filename")