Updated README.md

Author: Chris

README.md

@@ -1 +1,16 @@
 # ms-fragment-lister
+
+## What is it?
+
+This script will take exported mass listings from wsearch32 (a free software for mass spectrometry) and format all values so that:
+- the values are rounded
+- only values above 4% relative intensity are listed (this can be adjusted as needed)
+- the relative intensities appear in parentheses
+- the output is a CSV file
+
+
+## How to use
+
+Put the exported mass listings in the same folder as ``fragment-lister.py`` and run the script.
+
+Your Python installation must have pandas installed and the filename must end on ``.D.txt``. The script will work through **all** exported mass listings and produce one CSV output for every mass listing.