Coordinates interpolation

This example illustrates how OMAS can automatically interpolate data defined on coordinates that were already present in the data structure. This feature is extremely useful when different codes that have different computational grids need to read/write parts of the same data structure.

import numpy
from omas import *

print('A')
# SET: if a coordinate exists, then that is the coordinate that it is used
ods1 = ODS()
ods1['equilibrium.time_slice[0].profiles_1d.psi'] = numpy.linspace(0, 1, 10)
with omas_environment(ods1, coordsio={'equilibrium.time_slice[0].profiles_1d.psi': numpy.linspace(0, 1, 5)}):
    ods1['equilibrium.time_slice[0].profiles_1d.f'] = numpy.linspace(0, 1, 5)
print('ods1 f has length %d' % len(ods1['equilibrium.time_slice[0].profiles_1d.f']))
print()

A prints the following:

A
ods1 f has length 10

print('B')
# SET: if a does not exists, then that coordinate is set
ods2 = ODS()
with omas_environment(ods2, coordsio={'equilibrium.time_slice[0].profiles_1d.psi': numpy.linspace(0, 1, 5)}):
    ods2['equilibrium.time_slice[0].profiles_1d.pressure'] = numpy.linspace(0, 1, 5)
print('ods2 p has length %d' % len(ods2['equilibrium.time_slice[0].profiles_1d.pressure']))
print()

B the following:

B
ods2 p has length 5

print('C')
# SET: coordinates can be taken from existing ODSs
ods3 = ODS()
with omas_environment(ods3, coordsio=ods1):
    ods3['equilibrium.time_slice[0].profiles_1d.f'] = ods1['equilibrium.time_slice[0].profiles_1d.f']
with omas_environment(ods3, coordsio=ods2):
    ods3['equilibrium.time_slice[0].profiles_1d.pressure'] = ods2['equilibrium.time_slice[0].profiles_1d.pressure']
print('ods3 f has length %d' % len(ods3['equilibrium.time_slice[0].profiles_1d.f']))
print('ods3 p has length %d' % len(ods3['equilibrium.time_slice[0].profiles_1d.pressure']))
print()

C prints the following:

C
ods3 f has length 10
ods3 p has length 10

print('D')
# SET: order matters
ods4 = ODS()
with omas_environment(ods4, coordsio=ods2):
    ods4['equilibrium.time_slice[0].profiles_1d.pressure'] = ods2['equilibrium.time_slice[0].profiles_1d.pressure']
with omas_environment(ods4, coordsio=ods1):
    ods4['equilibrium.time_slice[0].profiles_1d.f'] = ods1['equilibrium.time_slice[0].profiles_1d.f']
print('ods4 f has length %d' % len(ods4['equilibrium.time_slice[0].profiles_1d.f']))
print('ods4 p has length %d' % len(ods4['equilibrium.time_slice[0].profiles_1d.pressure']))
print()

D prints the following:

D
ods4 f has length 5
ods4 p has length 5

print('E')
# GET: ods can be queried on different coordinates
with omas_environment(ods4, coordsio=ods1):
    print('ods4 f is returned with length %d' % len(ods4['equilibrium.time_slice[0].profiles_1d.f']))
print('ods4 f is returned with length %d' % len(ods4['equilibrium.time_slice[0].profiles_1d.f']))

E prints the following:

E
ods4 f is returned with length 10
ods4 f is returned with length 5