def __init__(self, type, owner = None, index = None, name = None):
"""Initialize type, owner, index, name.
:type type: a Type instance
:param type:
the type governs the kind of data that can be associated with this variable
:type owner: None or Apply instance
:param owner: the Apply instance which computes the value for this variable
:type index: None or int
:param index: the position of this Variable in owner.outputs
:type name: None or str
:param name: a string for pretty-printing and debugging
"""
self.tag = utils.scratchpad()
self.type = type
if owner is not None and not isinstance(owner, Apply):
raise TypeError("owner must be an Apply instance", owner)
self.owner = owner
if index is not None and not isinstance(index, int):
raise TypeError("index must be an int", index)
self.index = index
if name is not None and not isinstance(name, str):
raise TypeError("name must be a string", name)
self.name = name
def __init__(self, op, inputs, outputs):
"""Initialize attributes
:Parameters:
`op` : `Op` instance
initialize self.op
`inputs` : list of Variable instances
initialize self.inputs
`outputs` : list of Variable instances
initialize self.outputs
:note:
The owner field of each output in the outputs list will be set to self.
:note:
If an output element has an owner that is neither None nor self, then a ValueError
exception will be raised.
"""
self.op = op
self.inputs = []
self.tag = utils.scratchpad()
if not isinstance(inputs,(list,tuple)):
raise TypeError("The inputs of an Apply must be a list or tuple")
if not isinstance(outputs,(list,tuple)):
raise TypeError("The output of an Apply must be a list or tuple")
## filter inputs to make sure each element is a Variable
for input in inputs:
if isinstance(input, Variable):
self.inputs.append(input)
else:
raise TypeError("The 'inputs' argument to Apply must contain Variable instances, not %s" % input)
self.outputs = []
## filter outputs to make sure each element is a Variable
for i, output in enumerate(outputs):
if isinstance(output, Variable):
if output.owner is None:
output.owner = self
output.index = i
elif output.owner is not self or output.index != i:
raise ValueError("All output variables passed to Apply must belong to it.")
self.outputs.append(output)
else:
raise TypeError("The 'outputs' argument to Apply must contain Variable instances with no owner, not %s" % output)
