importFromAlignedReads {Genominator} | R Documentation

## Import aligned reads to database

### Description

This function takes a named list of `AlignedRead` objects (from the ShortRead package) and creates an `ExpData` object from them, with one column for each list element. Column names are taken from list names, which must be unique.

### Usage

    importFromAlignedReads(x, chrMap, dbFilename,
      tablename, overwrite = TRUE, deleteIntermediates = TRUE,
      readPosition = c("5prime", "left", "center"),
      verbose = getOption("verbose"), ...)

### Arguments

`x` | This argument can be one of two things: either a named list of objects of class `AlignedRead` or a named character vector of filenames. In both cases, the names of the object are used as column names inthe resulting database (not that it is not easy to change those names). Therefore the names of `x` needs to be present and non-empty and also to satisfy the requirements of column names in SQLite. If `x` is a list of `AlignedRead`, the column names needs to be unique. If `x` is a character vector of filenames, the names do not have to be unique, in which case two filenames with the same (column) name gets collapsed into the same column.
`chrMap` | A vector of chromosome names from the aligned output. On importation to the database, chromosome names will be converted to integers corresponding to position within the `chrMap` vector.
`dbFilename` | The filename of the database to which the data will be imported.
`tablename` | Name of database table to write output data to.
`overwrite` | Logical indicating whether database table referred to in `tablename` argument should be overwritten.
`deleteIntermediates` | Logical indicating whether intermediate database tables constructed in the process should be removed.
`readPosition` | How each read is assigned a unique genomic location. Default is `"5prime"` indicating that the location is the position of the 5' end of the reads, `"left"` indicates that the position of the left part of the read is used (5' end for reads mapping to the forward strand, 3' for reads mapping to the reverse strand), `"center"` indicates that the position of the center of the read is used.
`verbose` | Logical indicating whether details should be printed.
`...` | Additional arguments to be passed to `readAligned` from ShortRead.

### Details

The reads are aggregated and joined to form a database where each file/list element is a column. Positions are stored as the position of the 5' end of the reads (note that this differs from the convention for the `AlignedRead` class from ShortRead.) This can be changed by the `readPosition` argument.

If the `x` argument is a character vector of filenames, the function will require enough memory to parse each input file in turn. If there are duplicates in names of `x` the function requires enough memory to parse all files with the same column name at the same time.

If the `AlignedRead` class object has a `weights` column in its `alignData` slot, this `weights` column is used as the data to aggregate over.

### Value

Outputs an object of class `ExpData` with a column for each element of the `x` argument.

### Author(s)

James Bullard bullard@berkeley.edu, Kasper Daniel Hansen khansen@jhsph.edu

### See Also

See `Genominator` vignette for more information. See also `ExpData-class`, `AlignedRead-class` and `readAligned`.

### Examples

    ## Not run:
    require(ShortRead)
    require(yeastRNASeq)
    data("yeastAligned")
    chrMap <- levels(chromosome(yeastAligned[[1]]))
    eData <- importFromAlignedReads(yeastAligned, chrMap = chrMap,
                   dbFilename = tempfile(), tablename = "raw",
                   overwrite = TRUE)

    ## End(Not run)

[Package Genominator version 1.36.0 Index]