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Code Block
import imas
import getpass
import numpy as np
from imas import imasdef

#creating the Data Entry object 'data_entry' associated  to the pulse file with shot=15000, run=1, belonging to database 'data_access_tutorial' of the current user, using the MDS+ backend
data_entry = imas.DBEntry(imasdef.MDSPLUS_BACKEND, 'data_access_tutorial', 15000, 1)

#opening the pulse file handled by the Data Entry object previously created
data_entry.open() 

#creating the 'magnetics' IDS and initializing it
magnetics_ids = imas.magnetics() #creates a 'magnetics' IDS
magnetics_ids.ids_properties.homogeneous_time=1 #setting the homogeneous time (mandatory)
magnetics_ids.ids_properties.comment='IDS created for testing the IMAS Data Access layer' #setting the ids_properties.comment attribute
magnetics_ids.time=np.array([0.]) #the time(vector) basis must be not empty if homogeneous_time==1 otherwise an error will occur at runtime

#writing the 'magnetics' IDS
data_entry.put(magnetics_ids, 0) #writes magnetics data to the data_entry associated to the pulse file. The second argument 0 is the so-called IDS occurrence.

#closing the Data Entry
data_entry.close() 	 



Note

If you are using the HDF5 backend, you can check the content of the magnetics.h5 file using h5dump:

h5dump ~/public/imasdb/data_access_tutorial/3/15000/1/magnetics.h5



Let's extend the above example by adding the WEST data of the 10 first flux loops to the newly created 'magnetics' IDS.

Code Block
import imas
import getpass
import numpy as np
from imas import imasdef

#creating the Data Entry which handles the pulse file with shot=15000, run=1, belonging to database 'data_access_tutorial' of the current user, using the MDS+ backend
data_entry = imas.DBEntry(imasdef.MDSPLUS_BACKEND, 'data_access_tutorial', 15000, 1)

#opening the pulse file handled by the Data Entry object previously created
data_entry.open() 

#creating the 'magnetics' IDS and initializing it
magnetics_ids = imas.magnetics() #creates a 'magnetics' IDS
magnetics_ids.ids_properties.comment='IDS created for testing the IMAS Data Access layer' #setting the ids_properties.comment attribute

#adding the WEST data of the 10 first flux loops
nb_flux_loops = 10
west_data_entry = imas.DBEntry(imasdef.MDSPLUS_BACKEND, 'west', 54178, 0, 'g2lfleur')
west_magnetics_ids = west_data_entry.get('magnetics', 0) #reading occurrence 0
magnetics_ids.ids_properties.homogeneous_time=west_magnetics_ids.ids_properties.homogeneous_time #setting the homogeneous time (mandatory)
magnetics_ids.flux_loop.resize(nb_flux_loops)
for i in range(nb_flux_loops):
  magnetics_ids.flux_loop[i].flux.data = west_magnetics_ids.flux_loop[i].flux.data #copies data
  if west_magnetics_ids.ids_properties.homogeneous_time==0:
    magnetics_ids.flux_loop[i].flux.time = west_magnetics_ids.flux_loop[i].flux.time #copies the time basis in case WEST IDS arrays don't accept a common time basis

if west_magnetics_ids.ids_properties.homogeneous_time==1:
   magnetics_ids.time = west_magnetics_ids.time #copies the 'root' time basis in case WEST IDS arrays accept a common time basis
   
west_data_entry.close() #closing the WEST pulse file

#writing the 'magnetics' IDS
data_entry.put(magnetics_ids, 0) #writes magnetics data to the data_entry associated to the pulse file. The second argument 0 is the so-called IDS occurrence.

#closing the Data Entry
data_entry.close() 	 

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