cf.Field.__getitem__

Field.__getitem__(index)[source]

Called to implement evaluation of f[index].

f.__getitem__(index) <==> f[index]

The field is treated as if it were a single element field list containing itself, i.e. f[index] is equivalent to cf.FieldList(f)[index].

Examples 1:
>>> g = f[0]
>>> g = f[:1]
>>> g = f[1:]
Returns:
out : cf.Field or cf.FieldList

If index is the integer 0 or -1 then the field itself is returned. If index is a slice then a field list is returned which is either empty or else contains a single element of the field itself.

Examples 2:
>>> f[0] is f[-1] is f
True
>>> f[0:1].equals(cf.FieldList(f))   
True
>>> f[0:1][0] is f
True
>>> f[1:].equals(cf.FieldList())
True
>>> f[1:]       
[]
>>> f[-1::3][0] is f
True