methylKit (version 0.99.2)

regionCounts: Get regional counts for given GRanges or GRangesList object

Description

Convert methylRaw, methylRawDB, methylRawList, methylRawListDB, methylBase or methylBaseDB object into regional counts for a given GRanges or GRangesList object.

Usage

regionCounts(object,regions,cov.bases=0,strand.aware=FALSE,chunk.size,save.db,...)
# S4 method for methylRaw,GRanges
regionCounts(object, regions, cov.bases = 0,
  strand.aware = FALSE, chunk.size = 1e+06, save.db = FALSE, ...)
# S4 method for methylBase,GRanges
regionCounts(object, regions, cov.bases = 0,
  strand.aware = FALSE, chunk.size = 1e+06, save.db = FALSE, ...)
# S4 method for methylRaw,GRangesList
regionCounts(object, regions, cov.bases = 0,
  strand.aware = FALSE, chunk.size = 1e+06, save.db = FALSE, ...)
# S4 method for methylBase,GRangesList
regionCounts(object, regions,
  cov.bases = 0, strand.aware = FALSE, chunk.size = 1e+06,
  save.db = FALSE, ...)
# S4 method for methylRawList,GRanges
regionCounts(object, regions, cov.bases = 0,
  strand.aware = FALSE, chunk.size = 1e+06, save.db = FALSE, ...)
# S4 method for methylRawList,GRangesList
regionCounts(object, regions,
  cov.bases = 0, strand.aware = FALSE, chunk.size = 1e+06,
  save.db = FALSE, ...)
# S4 method for methylRawDB,GRanges
regionCounts(object, regions, cov.bases = 0,
  strand.aware = FALSE, chunk.size = 1e+06, save.db = TRUE, ...)
# S4 method for methylRawDB,GRangesList
regionCounts(object, regions,
  cov.bases = 0, strand.aware = FALSE, chunk.size = 1e+06,
  save.db = TRUE, ...)
# S4 method for methylRawListDB,GRanges
regionCounts(object, regions,
  cov.bases = 0, strand.aware = FALSE, chunk.size = 1e+06,
  save.db = TRUE, ...)
# S4 method for methylRawListDB,GRangesList
regionCounts(object, regions,
  cov.bases = 0, strand.aware = FALSE, chunk.size = 1e+06,
  save.db = TRUE, ...)
# S4 method for methylBaseDB,GRanges
regionCounts(object, regions, cov.bases = 0,
  strand.aware = FALSE, chunk.size = 1e+06, save.db = TRUE, ...)
# S4 method for methylBaseDB,GRangesList
regionCounts(object, regions,
  cov.bases = 0, strand.aware = FALSE, chunk.size = 1e+06,
  save.db = TRUE, ...)

Arguments

object

a methylRaw, methylRawDB, methylRawList, methylRawListDB, methylBase or methylBaseDB object

regions

a GRanges or GRangesList object. Make sure that the GRanges objects are unique in chr,start,end and strand columns.You can make them unique by using unique() function.

cov.bases

number minimum bases covered per region (Default:0). Only regions with base coverage above this threshold are returned.

strand.aware

if set to TRUE only CpGs that match the strand of the region will be summarized. (default:FALSE)

chunk.size

Number of rows to be taken as a chunk for processing the methylDB objects (default: 1e6)

save.db

A Logical to decide whether the resulting object should be saved as flat file database or not, default: explained in Details sections

...

optional Arguments used when save.db is TRUE

suffix A character string to append to the name of the output flat file database, only used if save.db is true, default actions: append “_filtered” to current filename if database already exists or generate new file with filename “sampleID_filtered” dbdir The directory where flat file database(s) should be stored, defaults to getwd(), working directory for newly stored databases and to same directory for already existing database dbtype The type of the flat file database, currently only option is "tabix" (only used for newly stored databases)

Value

a new methylRaw,methylBase or methylRawList object. If strand.aware is set to FALSE (default). Even though the resulting object will have the strand information of regions it will still contain methylation information from both strands.

Details

The parameter chunk.size is only used when working with methylRawDB, methylBaseDB or methylRawListDB objects, as they are read in chunk by chunk to enable processing large-sized objects which are stored as flat file database. Per default the chunk.size is set to 1M rows, which should work for most systems. If you encounter memory problems or have a high amount of memory available feel free to adjust the chunk.size.

The parameter save.db is per default TRUE for methylDB objects as methylRawDB, methylBaseDB or methylRawListDB, while being per default FALSE for methylRaw, methylBase or methylRawList. If you wish to save the result of an in-memory-calculation as flat file database or if the size of the database allows the calculation in-memory, then you might want to change the value of this parameter.

Examples

# NOT RUN {
data(methylKit)

# get the windows of interest as a GRanges object, this can be any set 
# of genomic locations
library(GenomicRanges)
my.win=GRanges(seqnames="chr21",
ranges=IRanges(start=seq(from=9764513,by=10000,length.out=20),width=5000) )

# getting counts per region
regional.methylRaw=regionCounts(object=methylRawList.obj, regions=my.win, 
cov.bases=0,strand.aware=FALSE)

# }