Mascot::MGF
A parser for Mascot Generic Format (MGF) files.
MGF Format
The Mascot::MGF object represents a file of MSMS spectra. See www.matrixscience.com/help/data_file_help.html#GEN for more information on this file format.
Mascot::MGF
A subclass of File, opens an MGF flat file to read entries using Enumerable syntax.
Mascot::MGF::Query
A simple object that represents individual MS/MS spectrum objects in an MGF file. I use “Query” instead of “Spectrum” to remain consistent with Mascot”s terminology.
Simple Usage Examples
Reading
require 'mascot/mgf'
# This opens a MGF file and builds an index of the query
# positions. The index is cached to the filesystem.
mgf = Mascot::MGF.open("some/file/path.mgf")
# Same thing as above, but does not cache the index to filesystem
mgf = Mascot::MGF.open("some/file/path.mgf",false)
# How many queries are in this file?
mgf.query_count
# Reads the next query from the read cursor position
query_string = mgf.readquery()
# Create a Mascot::MGF::Query from the query string query = Mascot::Query.new(query_string)
puts query.title
# Read the next query as a Mascot::MGF::Query object query = mgf.query() puts query.title
# puts cursor at begining of MGF file mgf.rewind
mgf.each_query do |query_object|
# do something with query...
end