DM_histogram.py

## @package python.demo.DM_histogram
# 
#   iterating over all points of an existing ODM within python 
#   (script works in python 2 and 3)
# 
 
from __future__ import print_function  # print function syntax as in python 3
import sys
 
from opals import pyDM
 
 
def DM_histogram(filename):
    # open the odm / pyDM.Datamanager.load parameters: filename(string), readOnly(bool) threadSafety(bool)
    dm = pyDM.Datamanager.load(filename, True, False)
 
    # if the dm wasn't opened successful exit function
    if not dm:
        print("Unable to open ODM '" + filename + "'")
        return
 
    f = pyDM.AddInfoLayoutFactory()
    f.addColumn(pyDM.ColumnSemantic.EchoNumber)
    layout = f.getLayout()
 
    print("Compute histogram of attribute 'EchoNumber'")
    histoSet = dm.getHistogramSet(layout)
 
    for histo in histoSet.histograms():
        for value, count in histo.values():
            print(value, "=", count)
 
    print("done")
 
 
if len(sys.argv) == 1:
    print("ODM parameter missing")
    sys.exit(-1)
 
DM_histogram(sys.argv[1])