spaCy/website/api/span.jade

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//- 💫 DOCS > API > SPAN
include ../_includes/_mixins
p A slice from a #[+api("doc") #[code Doc]] object.
+h(2, "init") Span.__init__
+tag method
p Create a Span object from the #[code slice doc[start : end]].
+aside-code("Example").
doc = nlp(u'Give it back! He pleaded.')
span = doc[1:4]
assert [t.text for t in span] == [u'it', u'back', u'!']
+table(["Name", "Type", "Description"])
+row
+cell #[code doc]
+cell #[code Doc]
+cell The parent document.
+row
+cell #[code start]
+cell int
+cell The index of the first token of the span.
+row
+cell #[code end]
+cell int
+cell The index of the first token after the span.
+row
+cell #[code label]
+cell int
+cell A label to attach to the span, e.g. for named entities.
+row
+cell #[code vector]
+cell #[code.u-break numpy.ndarray[ndim=1, dtype='float32']]
+cell A meaning representation of the span.
+row("foot")
+cell returns
+cell #[code Span]
+cell The newly constructed object.
+h(2, "getitem") Span.__getitem__
+tag method
p Get a #[code Token] object.
+aside-code("Example").
doc = nlp(u'Give it back! He pleaded.')
span = doc[1:4]
assert span[1].text == 'back'
+table(["Name", "Type", "Description"])
+row
+cell #[code i]
+cell int
+cell The index of the token within the span.
+row("foot")
+cell returns
+cell #[code Token]
+cell The token at #[code span[i]].
p Get a #[code Span] object.
+aside-code("Example").
doc = nlp(u'Give it back! He pleaded.')
span = doc[1:4]
assert span[1:3].text == 'back!'
+table(["Name", "Type", "Description"])
+row
+cell #[code start_end]
+cell tuple
+cell The slice of the span to get.
+row("foot")
+cell returns
+cell #[code Span]
+cell The span at #[code span[start : end]].
+h(2, "iter") Span.__iter__
+tag method
p Iterate over #[code Token] objects.
+aside-code("Example").
doc = nlp(u'Give it back! He pleaded.')
span = doc[1:4]
assert [t.text for t in span] == ['it', 'back', '!']
+table(["Name", "Type", "Description"])
+row("foot")
+cell yields
+cell #[code Token]
+cell A #[code Token] object.
+h(2, "len") Span.__len__
+tag method
p Get the number of tokens in the span.
+aside-code("Example").
doc = nlp(u'Give it back! He pleaded.')
span = doc[1:4]
assert len(span) == 3
+table(["Name", "Type", "Description"])
+row("foot")
+cell returns
+cell int
+cell The number of tokens in the span.
+h(2, "set_extension") Span.set_extension
+tag classmethod
+tag-new(2)
p
| Define a custom attribute on the #[code Span] which becomes available via
| #[code Span._]. For details, see the documentation on
| #[+a("/usage/processing-pipelines#custom-components-attributes") custom attributes].
+aside-code("Example").
from spacy.tokens.span import Span
city_getter = lambda span: span.text in ('New York', 'Paris', 'Berlin')
Span.set_extension('has_city', getter=city_getter)
doc = nlp(u'I like New York in Autumn')
assert doc[1:4]._.has_city
+table(["Name", "Type", "Description"])
+row
+cell #[code name]
+cell unicode
+cell
| Name of the attribute to set by the extension. For example,
| #[code 'my_attr'] will be available as #[code span._.my_attr].
+row
+cell #[code default]
+cell -
+cell
| Optional default value of the attribute if no getter or method
| is defined.
+row
+cell #[code method]
+cell callable
+cell
| Set a custom method on the object, for example
| #[code span._.compare(other_span)].
+row
+cell #[code getter]
+cell callable
+cell
| Getter function that takes the object and returns an attribute
| value. Is called when the user accesses the #[code ._] attribute.
+row
+cell #[code setter]
+cell callable
+cell
| Setter function that takes the #[code Span] and a value, and
| modifies the object. Is called when the user writes to the
| #[code Span._] attribute.
+h(2, "get_extension") Span.get_extension
+tag classmethod
+tag-new(2)
p
| Look up a previously registered extension by name. Returns a 4-tuple
| #[code.u-break (default, method, getter, setter)] if the extension is
| registered. Raises a #[code KeyError] otherwise.
+aside-code("Example").
from spacy.tokens.span import Span
Span.set_extension('is_city', default=False)
extension = Span.get_extension('is_city')
assert extension == (False, None, None, None)
+table(["Name", "Type", "Description"])
+row
+cell #[code name]
+cell unicode
+cell Name of the extension.
+row("foot")
+cell returns
+cell tuple
+cell
| A #[code.u-break (default, method, getter, setter)] tuple of the
| extension.
+h(2, "has_extension") Span.has_extension
+tag classmethod
+tag-new(2)
p Check whether an extension has been registered on the #[code Span] class.
+aside-code("Example").
from spacy.tokens.span import Span
Span.set_extension('is_city', default=False)
assert Span.has_extension('is_city')
+table(["Name", "Type", "Description"])
+row
+cell #[code name]
+cell unicode
+cell Name of the extension to check.
+row("foot")
+cell returns
+cell bool
+cell Whether the extension has been registered.
+h(2, "similarity") Span.similarity
+tag method
+tag-model("vectors")
p
| Make a semantic similarity estimate. The default estimate is cosine
| similarity using an average of word vectors.
+aside-code("Example").
doc = nlp(u'green apples and red oranges')
green_apples = doc[:2]
red_oranges = doc[3:]
apples_oranges = green_apples.similarity(red_oranges)
oranges_apples = red_oranges.similarity(green_apples)
assert apples_oranges == oranges_apples
+table(["Name", "Type", "Description"])
+row
+cell #[code other]
+cell -
+cell
| The object to compare with. By default, accepts #[code Doc],
| #[code Span], #[code Token] and #[code Lexeme] objects.
+row("foot")
+cell returns
+cell float
+cell A scalar similarity score. Higher is more similar.
+h(2, "to_array") Span.to_array
+tag method
+tag-new(2)
p
| Given a list of #[code M] attribute IDs, export the tokens to a numpy
| #[code ndarray] of shape #[code (N, M)], where #[code N] is the length of
| the document. The values will be 32-bit integers.
+aside-code("Example").
from spacy.attrs import LOWER, POS, ENT_TYPE, IS_ALPHA
doc = nlp(u'I like New York in Autumn.')
span = doc[2:3]
# All strings mapped to integers, for easy export to numpy
np_array = span.to_array([LOWER, POS, ENT_TYPE, IS_ALPHA])
+table(["Name", "Type", "Description"])
+row
+cell #[code attr_ids]
+cell list
+cell A list of attribute ID ints.
+row("foot")
+cell returns
+cell #[code.u-break numpy.ndarray[long, ndim=2]]
+cell
| A feature matrix, with one row per word, and one column per
| attribute indicated in the input #[code attr_ids].
+h(2, "merge") Span.merge
+tag method
p Retokenize the document, such that the span is merged into a single token.
+aside-code("Example").
doc = nlp(u'I like New York in Autumn.')
span = doc[2:3]
span.merge()
assert len(doc) == 6
assert doc[2].text == 'New York'
+table(["Name", "Type", "Description"])
+row
+cell #[code **attributes]
+cell -
+cell
| Attributes to assign to the merged token. By default, attributes
| are inherited from the syntactic root token of the span.
+row("foot")
+cell returns
+cell #[code Token]
+cell The newly merged token.
+h(2, "root") Span.root
+tag property
+tag-model("parse")
p
| The token within the span that's highest in the parse tree. If there's a
| tie, the earliest is preferred.
+aside-code("Example").
doc = nlp(u'I like New York in Autumn.')
i, like, new, york, in_, autumn, dot = range(len(doc))
assert doc[new].head.text == 'York'
assert doc[york].head.text == 'like'
new_york = doc[new:york+1]
assert new_york.root.text == 'York'
+table(["Name", "Type", "Description"])
+row("foot")
+cell returns
+cell #[code Token]
+cell The root token.
+h(2, "lefts") Span.lefts
+tag property
+tag-model("parse")
p Tokens that are to the left of the span, whose head is within the span.
+aside-code("Example").
doc = nlp(u'I like New York in Autumn.')
lefts = [t.text for t in doc[3:7].lefts]
assert lefts == [u'New']
+table(["Name", "Type", "Description"])
+row("foot")
+cell yields
+cell #[code Token]
+cell A left-child of a token of the span.
+h(2, "rights") Span.rights
+tag property
+tag-model("parse")
p Tokens that are to the right of the span, whose head is within the span.
+aside-code("Example").
doc = nlp(u'I like New York in Autumn.')
rights = [t.text for t in doc[2:4].rights]
assert rights == [u'in']
+table(["Name", "Type", "Description"])
+row("foot")
+cell yields
+cell #[code Token]
+cell A right-child of a token of the span.
+h(2, "subtree") Span.subtree
+tag property
+tag-model("parse")
p Tokens that descend from tokens in the span, but fall outside it.
+aside-code("Example").
doc = nlp(u'Give it back! He pleaded.')
subtree = [t.text for t in doc[:3].subtree]
assert subtree == [u'Give', u'it', u'back', u'!']
+table(["Name", "Type", "Description"])
+row("foot")
+cell yields
+cell #[code Token]
+cell A descendant of a token within the span.
+h(2, "has_vector") Span.has_vector
+tag property
+tag-model("vectors")
p
| A boolean value indicating whether a word vector is associated with the
| object.
+aside-code("Example").
doc = nlp(u'I like apples')
assert doc[1:].has_vector
+table(["Name", "Type", "Description"])
+row("foot")
+cell returns
+cell bool
+cell Whether the span has a vector data attached.
+h(2, "vector") Span.vector
+tag property
+tag-model("vectors")
p
| A real-valued meaning representation. Defaults to an average of the
| token vectors.
+aside-code("Example").
doc = nlp(u'I like apples')
assert doc[1:].vector.dtype == 'float32'
assert doc[1:].vector.shape == (300,)
+table(["Name", "Type", "Description"])
+row("foot")
+cell returns
+cell #[code.u-break numpy.ndarray[ndim=1, dtype='float32']]
+cell A 1D numpy array representing the span's semantics.
+h(2, "vector_norm") Span.vector_norm
+tag property
+tag-model("vectors")
p
| The L2 norm of the span's vector representation.
+aside-code("Example").
doc = nlp(u'I like apples')
doc[1:].vector_norm # 4.800883928527915
doc[2:].vector_norm # 6.895897646384268
assert doc[1:].vector_norm != doc[2:].vector_norm
+table(["Name", "Type", "Description"])
+row("foot")
+cell returns
+cell float
+cell The L2 norm of the vector representation.
+h(2, "attributes") Attributes
+table(["Name", "Type", "Description"])
+row
+cell #[code doc]
+cell #[code Doc]
+cell The parent document.
+row
+cell #[code sent]
+cell #[code Span]
+cell The sentence span that this span is a part of.
+row
+cell #[code start]
+cell int
+cell The token offset for the start of the span.
+row
+cell #[code end]
+cell int
+cell The token offset for the end of the span.
+row
+cell #[code start_char]
+cell int
+cell The character offset for the start of the span.
+row
+cell #[code end_char]
+cell int
+cell The character offset for the end of the span.
+row
+cell #[code text]
+cell unicode
+cell A unicode representation of the span text.
+row
+cell #[code text_with_ws]
+cell unicode
+cell
| The text content of the span with a trailing whitespace character
| if the last token has one.
+row
+cell #[code label]
+cell int
+cell The span's label.
+row
+cell #[code label_]
+cell unicode
+cell The span's label.
+row
+cell #[code lemma_]
+cell unicode
+cell The span's lemma.
+row
+cell #[code ent_id]
+cell int
+cell The hash value of the named entity the token is an instance of.
+row
+cell #[code ent_id_]
+cell unicode
+cell The string ID of the named entity the token is an instance of.