owmeta.evidence module¶
-
class
owmeta.evidence.
Evidence
(**kwargs)[source]¶ Bases:
owmeta_core.dataobject.DataObject
A representation which provides evidence, for a group of statements.
Attaching evidence to an set of statements is done like this:
>>> from owmeta.connection import Connection >>> from owmeta.evidence import Evidence >>> from owmeta_core.context import Context
Declare contexts:
>>> ACTX = Context(ident="http://example.org/data/some_statements") >>> BCTX = Context(ident="http://example.org/data/some_other_statements") >>> EVCTX = Context(ident="http://example.org/data/some_statements#evidence")
Make statements in
ACTX
andBCTX
contexts:>>> ACTX(Connection)(pre_cell="VA11", post_cell="VD12", number=3) >>> BCTX(Connection)(pre_cell="VA11", post_cell="VD12", number=2)
In
EVCTX
, state that a that a certain document supports the set of statements inACTX
, but refutes the set of statements inBCTX
:>>> doc = EVCTX(Document)(author='White et al.', date='1986') >>> EVCTX(Evidence)(reference=doc, supports=ACTX.rdf_object) >>> EVCTX(Evidence)(reference=doc, refutes=BCTX.rdf_object)
Finally, save the contexts:
>>> ACTX.save_context() >>> BCTX.save_context() >>> EVCTX.save_context()
One note about the
reference
predicate: the reference should, ideally, be an unambiguous link to a peer-reviewed piece of scientific literature detailing methods and data analysis that supports the set of statements. However, in gather data from pre-existing sources, going to that level of specificity may be difficult due to deficient query capability at the data source. In such cases, a broader reference, such as aWebsite
with information which guides readers to a peer-reviewed article supporting the statement is sufficient.-
defined_augment
()[source]¶ This fuction must return False if
identifier_augment()
would raise anIdentifierMissingException
. Override it when defining a non-standard identifier for subclasses of DataObjects.
-
identifier_augment
()[source]¶ Override this method to define an identifier in lieu of one explicity set.
One must also override
defined_augment()
to return True whenever this method could return a valid identifier.IdentifierMissingException
should be raised if an identifier cannot be generated by this method.Raises: IdentifierMissingException
-
reference
¶ The resource providing evidence supporting/refuting the attached context
-
refutes
¶ A context naming a set of statements which are refuted by the attached reference
-
supports
¶ A context naming a set of statements which are supported by the attached reference
-
-
owmeta.evidence.
evidence_for
(qctx, ctx, evctx=None)[source]¶ Returns an iterable of Evidence
Parameters: - qctx :
object
an object supported by evidence. If the object is a
Context
with no identifier, then the query considers statements ‘staged’ (rather than stored) in the context- ctx :
Context
Context that bounds where we look for statements about
qctx
. The contexts for statements found in this context are the actual targets of Evidence.supports statements.- evctx :
Context
if the Evidence.supports statements should be looked for somewhere other than
ctx
, that can be specified in evctx. optional
- qctx :