HedTag¶

class HedTag(hed_string, hed_schema, span=None, def_dict=None)[source]

A single HED tag.

Notes

HedTag is a smart class in that it keeps track of its original value and positioning as well as pointers to the relevant HED schema information, if relevant.

Methods

`HedTag.__init__`(hed_string, hed_schema[, ...])	Creates a HedTag.
`HedTag.base_tag_has_attribute`(tag_attribute)	Check to see if the tag has a specific attribute.
`HedTag.casefold`()	Convenience function, equivalent to str(self).casefold().
`HedTag.copy`()	Return a deep copy of this tag.
`HedTag.get_stripped_unit_value`(extension_text)	Return the extension divided into value and units, if the units are valid.
`HedTag.get_tag_unit_class_units`()	Get the unit class units associated with a particular tag.
`HedTag.has_attribute`(attribute)	Return True if this is an attribute this tag has.
`HedTag.is_basic_tag`()	Return True if a known tag with no extension or value.
`HedTag.is_column_ref`()	Return if this tag is a column reference from a sidecar.
`HedTag.is_placeholder`()	Returns if this tag has a placeholder in it.
`HedTag.is_takes_value_tag`()	Return True if this is a takes value tag.
`HedTag.is_unit_class_tag`()	Return True if this is a unit class tag.
`HedTag.is_value_class_tag`()	Return True if this is a value class tag.
`HedTag.lower`()	Convenience function, equivalent to str(self).lower().
`HedTag.replace_placeholder`(placeholder_value)	If tag has a placeholder character(#), replace with value.
`HedTag.tag_exists_in_schema`()	Return whether the schema entry for this tag exists.
`HedTag.tag_modified`()	Return True if tag has been modified from original.
`HedTag.value_as_default_unit`()	Return the value converted to default units if possible.

Attributes

`HedTag.attributes`	Return a dict of all the attributes this tag has.
`HedTag.base_tag`	Long form without value or extension.
`HedTag.default_unit`	Get the default unit class unit for this tag.
`HedTag.expandable`	Return what this expands to.
`HedTag.expanded`	Return if this is currently expanded or not.
`HedTag.extension`	Get the extension or value of tag.
`HedTag.long_tag`	Long form including value or extension.
`HedTag.org_base_tag`	Original form without value or extension.
`HedTag.org_tag`	Return the original unmodified tag.
`HedTag.schema_namespace`	Library namespace for this tag if one exists.
`HedTag.short_base_tag`	Short form without value or extension.
`HedTag.short_tag`	Short form including value or extension.
`HedTag.tag`	Returns the tag.
`HedTag.unit_classes`	Return a dict of all the unit classes this tag accepts.
`HedTag.value_classes`	Return a dict of all the value classes this tag accepts.

HedTag.__init__(hed_string, hed_schema, span=None, def_dict=None)[source]¶

Creates a HedTag.

Parameters:

hed_string (str) – Source HED string for this tag.
hed_schema (HedSchema) – A parameter for calculating canonical forms on creation.
span (int, int) – The start and end indexes of the tag in the hed_string.
def_dict (DefinitionDict or None) – The def dict to use to identify def/def expand tags.

HedTag.base_tag_has_attribute(tag_attribute)[source]¶

Check to see if the tag has a specific attribute.

This is primarily used to check for things like TopLevelTag on Definitions and similar.

Parameters:: tag_attribute (str) – A tag attribute.
Returns:: True if the tag has the specified attribute. False, if otherwise.
Return type:: bool

HedTag.casefold()[source]¶: Convenience function, equivalent to str(self).casefold().

HedTag.copy()[source]¶

Return a deep copy of this tag.

Returns:: The copied group.
Return type:: HedTag

HedTag.get_stripped_unit_value(extension_text)[source]¶

Return the extension divided into value and units, if the units are valid.

Parameters:: extension_text (str) – The text to split, in case it’s a portion of a tag.
Returns:: The extension portion with the units removed. unit (str or None): None if no valid unit found.
Return type:: stripped_unit_value (str)

Examples

‘Duration/3 ms’ will return ‘3’

HedTag.get_tag_unit_class_units()[source]¶

Get the unit class units associated with a particular tag.

Returns:: A list containing the unit class units associated with a particular tag or an empty list.
Return type:: list

HedTag.has_attribute(attribute)[source]¶

Return True if this is an attribute this tag has.

Parameters:: attribute (str) – Name of the attribute.
Returns:: True if this tag has the attribute.
Return type:: bool

HedTag.is_basic_tag()[source]¶

Return True if a known tag with no extension or value.

Returns:: True if this is a known tag without extension or value.
Return type:: bool

HedTag.is_column_ref()[source]¶

Return if this tag is a column reference from a sidecar.

You should only see these if you are directly accessing sidecar strings, tools should remove them otherwise.

Returns:: Returns True if this is a column ref.
Return type:: bool

HedTag.is_placeholder()[source]¶

Returns if this tag has a placeholder in it.

Returns:: True if it has a placeholder
Return type:: has_placeholder(bool)

HedTag.is_takes_value_tag()[source]¶

Return True if this is a takes value tag.

Returns:: True if this is a takes value tag.
Return type:: bool

HedTag.is_unit_class_tag()[source]¶

Return True if this is a unit class tag.

Returns:: True if this is a unit class tag.
Return type:: bool

HedTag.is_value_class_tag()[source]¶

Return True if this is a value class tag.

Returns:: True if this is a tag with a value class.
Return type:: bool

HedTag.lower()[source]¶: Convenience function, equivalent to str(self).lower().

HedTag.replace_placeholder(placeholder_value)[source]¶

If tag has a placeholder character(#), replace with value.

Parameters:: placeholder_value (str) – Value to replace placeholder with.

HedTag.tag_exists_in_schema()[source]¶

Return whether the schema entry for this tag exists.

Returns:: True if this tag exists.
Return type:: bool

Notes

This does NOT assure this is a valid tag.

HedTag.tag_modified()[source]¶

Return True if tag has been modified from original.

Returns:: Return True if the tag is modified.
Return type:: bool

Notes

Modifications can include adding a column name_prefix.

HedTag.value_as_default_unit()[source]¶

Return the value converted to default units if possible.

Returns None if the units are invalid.(No default unit or invalid).

Returns:

The extension value as default units.: If there are no default units, returns None.

Return type:

value (float or None)

Examples

‘Duration/300 ms’ will return .3

HedTag.attributes¶

Return a dict of all the attributes this tag has.

Returns empty dict if this is not a value tag.

Returns:: A dict of attributes this tag has.
Return type:: dict

Notes

Returns empty dict if this is not a unit class tag.
The dictionary has unit name as the key and HedSchemaEntry as value.

HedTag.base_tag¶

Long form without value or extension.

Returns:: The long form of the tag, without value or extension.
Return type:: base_tag (str)

HedTag.default_unit¶

Get the default unit class unit for this tag.

Only a tag with a single unit class can have default units.

Returns:: the default unit entry for this tag, or None
Return type:: unit(UnitEntry or None)

HedTag.expandable¶

Return what this expands to.

This is primarily used for Def/Def-expand tags at present.

Lazily set the first time it’s called.

Returns:: Returns the expanded form of this tag.
Return type:: HedGroup or HedTag or None

HedTag.expanded¶

Return if this is currently expanded or not.

Will always be False unless expandable is set. This is primarily used for Def/Def-expand tags at present.

Returns:: Returns True if this is currently expanded.
Return type:: bool

HedTag.extension¶

Get the extension or value of tag.

Generally this is just the portion after the last slash. Returns an empty string if no extension or value.

Returns:: The tag name.
Return type:: str

Notes

This tag must have been computed first.

HedTag.long_tag¶

Long form including value or extension.

Returns:: The long form of this tag.
Return type:: str

HedTag.org_base_tag¶

Original form without value or extension.

Returns:: The original form of the tag, without value or extension.
Return type:: base_tag (str)

Notes

Warning: This could be empty if the original tag had a name_prefix prepended. e.g. a column where “Label/” is prepended, thus the column value has zero base portion.

HedTag.org_tag¶

Return the original unmodified tag.

Returns:: The original unmodified tag.
Return type:: str

HedTag.schema_namespace¶

Library namespace for this tag if one exists.

Returns:: The library namespace, including the colon.
Return type:: namespace (str)

HedTag.short_base_tag¶

Short form without value or extension.

Returns:: The short non-extension port of a tag.
Return type:: base_tag (str)

Notes

ParentNodes/Def/DefName would return just “Def”.

HedTag.short_tag¶

Short form including value or extension.

Returns:: The short form of the tag, including value or extension.
Return type:: short_tag (str)

HedTag.tag¶

Returns the tag.

Returns the original tag if no user form set.

Returns:: The custom set user form of the tag.
Return type:: tag (str)

HedTag.unit_classes¶

Return a dict of all the unit classes this tag accepts.

Returns:: A dict of unit classes this tag accepts.
Return type:: unit_classes (dict)

Notes

Returns empty dict if this is not a unit class tag.
The dictionary has unit name as the key and HedSchemaEntry as value.

HedTag.value_classes¶

Return a dict of all the value classes this tag accepts.

Returns:: A dictionary of HedSchemaEntry value classes this tag accepts.
Return type:: dict

Notes

Returns empty dict if this is not a value class.
The dictionary has unit name as the key and HedSchemaEntry as value.