isCentroidedFromFile {MSnbase} | R Documentation

## Get mode from mzML data file

### Description

The function extracts the mode (profile or centroided) from the raw mass spectrometry file by parsing the mzML file directly. If the object `x` stems from any other type of file, `NA`s are returned.

### Usage

    isCentroidedFromFile(x)

### Arguments

`x` | An object of class OnDiskMSnExp.

### Details

This function is much faster than `isCentroided()`, which estimates mode from the data, but is limited to data stemming from mzML files which are still available in their original location (and accessed with `fileNames(x)`).

### Value

A named `logical` vector of the same length as `x`.

### Author(s)

Laurent Gatto

### Examples

    library("msdata")
    f <- proteomics(full.names = TRUE,
                    pattern = "TMT_Erwinia_1uLSike_Top10HCD_isol2_45stepped_60min_01.mzML.gz")
    x <- readMSData(f, mode = "onDisk")
    table(isCentroidedFromFile(x), msLevel(x))

[Package MSnbase version 2.4.2 Index]