Source code for pydicom.multival

"""Code for multi-value data elements values,
or any list of items that must all be the same type.

# Copyright (c) 2009-2012 Darcy Mason
# This file is part of pydicom, relased under an MIT-style license.
#    See the file LICENSE included with this distribution, also
#    available at
from collections import MutableSequence

[docs]class MultiValue(MutableSequence): """Class to hold any multi-valued DICOM value, or any list of items that are all of the same type. This class enforces that any items added to the list are of the correct type, by calling the constructor on any items that are added. Therefore, the constructor must behave nicely if passed an object that is already its type. The constructor should raise TypeError if the item cannot be converted. Note, however, that DS and IS types can be a blank string '' rather than an instance of their classes. """ def __init__(self, type_constructor, iterable): """Initialize the list of values :param type_constructor: a constructor for the required type for all list items. Could be the class, or a factory function. For DICOM mult-value data elements, this will be the class or type corresponding to the VR. :param iterable: an iterable (e.g. list, tuple) of items to initialize the MultiValue list """ from pydicom.valuerep import DSfloat, DSdecimal, IS def number_string_type_constructor(x): return self.type_constructor(x) if x != '' else x self._list = list() self.type_constructor = type_constructor if type_constructor in (DSfloat, IS, DSdecimal): type_constructor = number_string_type_constructor for x in iterable: self._list.append(type_constructor(x))
[docs] def insert(self, position, val): self._list.insert(position, self.type_constructor(val))
def __setitem__(self, i, val): """Set an item of the list, making sure it is of the right VR type""" if isinstance(i, slice): val = [self.type_constructor(v) for v in val] self._list.__setitem__(i, val) else: self._list.__setitem__(i, self.type_constructor(val)) def __str__(self): lines = [str(x) for x in self] return "['" + "', '".join(lines) + "']" __repr__ = __str__ def __len__(self): return len(self._list) def __getitem__(self, index): return self._list[index] def __delitem__(self, index): del self._list[index] def __iter__(self): return iter(self._list) def __eq__(self, other): return self._list == other def __ne__(self, other): return self._list != other def sort(self, key=None, reverse=False): self._list.sort(key=key, reverse=reverse)