emuR (version 0.1.9)

requery_seq: Requery sequential context of segment list in an emuDB

Description

Function to requery sequential context of a segment list queried from an emuDB

Usage

requery_seq(emuDBhandle, seglist, offset = 0, offsetRef = "START", length = 1, ignoreOutOfBounds = FALSE)

Arguments

emuDBhandle

emuDB handle as returned by load_emuDB

seglist

segment list to requery on (type: 'emuRsegs')

offset

start item offset in sequence (default is 0, meaning the start or end item of the input segment)

offsetRef

reference item for offset: 'START' for first and 'END' for last item of segment

length

item length of segments in the returned segment list

ignoreOutOfBounds

ignore result segments that are out of bundle bounds

Value

result set object of class 'emuRsegs' containing the requeried segments

Details

Builds a new segment list on the same hierarchical level and the same length as the segment list given in seglist. The resulting segments usually have different start position and length (in terms of items of the respective level) controlled by the offset,offsetRef and length parameters. A segment here is defined as a single item or a chain of items from the respective level, e.g. if a level in a bundle instance has labels 'a', 'b' and 'c' in that order, 'a' or 'a->b' oder 'a->b->c' are all valid segments, but not 'a->c'. offsetRef determines if the position offset is referenced to the start or the end item of the segments in the input list seglist; parameter offset determines the offset of the resulting item start position to this reference item; parameter length sets the item length of the result segments. If the requested segments are out of bundle item boundaries and parameter ignoreOutOfBounds is FALSE (the default), an error is generated. To get residual resulting segments that lie within the bounds the ignoreOutOfBounds parameter can be set to TRUE. The returned segment list is usually of the same length and order as the input seglist; if ignoreOutOfBounds=FALSE, the resulting segment list may be out of sync.

See Also

query requery_hier emuRsegs

Examples

## Not run: 
# 
# ##################################
# # prerequisite: loaded ae emuDB 
# # (see ?load_emuDB for more information)
# 
# ## Requery previous item of 'p' on level 'Phonetic'
# sl1 = query(ae, "Phonetic == p")
# 
# requery_seq(ae, sl1, offset = -1)
# 
# ## Requery context (adding previuos and following elements) of 'p' on phonetic level
# 
# requery_seq(ae, sl1, offset = -1, length = 3)
# 
# ## Requery previous item of n->t sequence
# sl2 = query(ae, "[Phoneme == n -> Phoneme == t]")
# 
# requery_seq(ae, sl2, offset = -1)
# 
# ## Requery last item within n->t sequence
# 
# requery_seq(ae, sl2, offsetRef = 'END')
# 
# ## Requery following item after n->t sequence
# 
# requery_seq(ae, sl2, offset = 1, offsetRef = 'END')
# 
# ## Requery context (previous and following items) of n->t sequence
# 
# requery_seq(ae, sl2, offset = -1, length = 4)
# 
# ## Requery next word contexts (sequence includes target word)
# 
# sl3 = query(ae, "Text == to")
# requery_seq(ae, sl3, length = 2)
# 
# ## Requery following two word contexts, ignoring segment 
# ## sequences that are out of bundle end bounds 
# requery_seq(ae, sl3, length = 3, ignoreOutOfBounds = TRUE)
# 
# ## End(Not run)