Source code for fastr.core.dimension

# Copyright 2011-2014 Biomedical Imaging Group Rotterdam, Departments of
# Medical Informatics and Radiology, Erasmus MC, Rotterdam, The Netherlands
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
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from abc import ABCMeta, abstractproperty

import sympy

from fastr import exceptions


[docs]class Dimension(object): """ A class representing a dimension. It contains the name and size of the dimension. """
[docs] def __init__(self, name, size): """ The constructor for the dimension. :param str name: Name of the dimension :param size: Size fo the dimension :type size: int or sympy.Symbol """ if not isinstance(name, str): raise exceptions.FastrTypeError("Dimension.name should be a str, " "found [{}] {}".format(type(name).__name__, size)) if not isinstance(size, (int, sympy.Symbol)): raise exceptions.FastrTypeError("Dimension.size should be an int or" " sympy.Symbol, found [{}] {}".format(type(size).__name__, size)) if isinstance(size, int) and size < 0: raise exceptions.FastrValueError("Dimension.size should be non-negative") self.name = name self.size = size
[docs]class HasDimensions(object): """ A Mixin class for any object that has a notion of dimensions and size. It uses the dimension property to expose the dimension name and size. """ __metaclass__ = ABCMeta @abstractproperty def dimensions(self): """ The dimensions has to be implemented by any subclass. It has to provide a tuple of Dimensions. :return: dimensions :rtype: tuple """ @property def dimnames(self): """ A tuple containing the dimension names of this object. All items of the tuple are of type str. """ return tuple(x.name for x in self.dimensions) @property def size(self): """ A tuple containing the size of this object. All items of the tuple are of type int or sympy.Symbol. """ return tuple(x.size for x in self.dimensions)