grabMzxmlSpectraMzInt {RaMS}

Extract the mass-to-charge data from the spectra of an mzXML nodeset

Description

The mz and intensity information of mzXML files are encoded as a binary array, sometimes compressed via gzip or zlib or numpress. This code finds all the m/z-int binary arrays and converts them back to the original measurements. See https://github.com/ProteoWizard/pwiz/issues/1301

Usage

grabMzxmlSpectraMzInt(xml_nodes, file_metadata)

Arguments

xml_nodes

An xml_nodeset object corresponding to the spectra collected by the mass spectrometer, usually produced by applying 'xml_find_all' to an MS1 or MS2 nodeset.

file_metadata

Information about the file used to decode the binary arrays containing m/z and intensity information. Here, the compression and mz precision information is relevant.

Value

A numeric vector of masses, many for each scan.