segram.symbols module

Symbols are used for denoting discrete enumerable types of entities of a given class, for instance semantic roles such as subjects or direct objects of verb.

The advantage of using symbols, implemented based on enum.Flag, is that it allows combining and filtering based on symbols using binary boolean operators.

class segram.symbols.POS(value, names=None, *, module=None, qualname=None, type=None, start=1, boundary=None)[source]

Bases: Symbol

Universal dependencies POS tags.

See definitions here.

class segram.symbols.Role(value, names=None, *, module=None, qualname=None, type=None, start=1, boundary=None)[source]

Bases: Symbol

Syntactic role symbols.

Unlike POS tags (and standard syntactic dependencies), syntactic roles are not fixed but may be phrase-specific. Thus, the same token can play different syntactic roles in different phrases, e.g. it can be a direct object in one verb phrase and a subject in another.

Moreover, roles are used for marking tokens of which functions can not be simply determined by their POS or dependency tags, e.g. negations, even though such roles may often be fixed and not phrase-specific.

Notes

Currently, roles are used primarily for printing purposes, i.e. coloring tokens in console outputs, and therefore also selected, most important, roles are defined. Moreover, it is still an open question what roles should be defined.

VERB: Verb or a verb-like predicate.

NOUN: Noun, typically the head of a noun phrase.

SUBJ: Subject (active, passive, nominal or clausal etc.).

DOBJ: Direct object of a verb or a description.

IOBJ: Indirect object of a verb (dative).

PREP: Preposition.

POBJ: Object of a preposition.

PROOT: Root of a preposition.

DESC: Description. This includes adjectives, adverbs, and adjectival and adverbial modifiers as well as any other sort of construction used to directly describe nouns, verbs and prepositions.

BG: Background element that should be not emphasized visually when printing, e.g. printed in gray.

NEG: Negation.

QMARK: Question mark.

EXCLAM: Exclamation mark.

INTJ: Interjection.

class segram.symbols.Tense(value, names=None, *, module=None, qualname=None, type=None, start=1, boundary=None)[source]

Bases: Symbol

Tense symbols.

PAST: Past tense

PRESENT: Present tense.

FUTURE: Future tense.

class segram.symbols.Modal(value, names=None, *, module=None, qualname=None, type=None, start=1, boundary=None)[source]

Bases: Symbol

Modal symbols.

NULL: No modality.

ABILITY: Ability mood (e.g. ‘can’ or ‘could’ in English).

POSSIBILITY: POssibility mode (e.g. ‘may’ or ‘might’ in English).

NECESSITY: Necessity mode (e.g. ‘must’ in English).

OBLIGATION: Obligation mode (e.g. ‘shoud’ or ‘ought to’ in English).

NEED: Need moge (e.g. ‘need’ in English).

class segram.symbols.Mood(value, names=None, *, module=None, qualname=None, type=None, start=1, boundary=None)[source]

Bases: Symbol

Grammatical mood.

Currently only few selected moods are implemented.

REAL: Standard indicative mood (realis).

IMP: Imperative mood.