In Reply Refer To:
Mail Stop 412 November 14, 2001
OFFICE OF WATER QUALITY TECHNICAL MEMORANDUM 2002.03
Subject: National Water Quality
System (NWIS) QWDATA Rounding Code—update to fix errors
A script has been written to update the NWIS QWDATA ‘user rounding code’
for several hundred parameter codes.
The ‘user rounding code’ (has been called the precision code) is the
integer stored with each result in the database that defines the number of
decimal places or significant figures when a user selects the 'user rounding'
option for output.
The update will
repair problems that were introduced into the ‘user rounding code’ from several
sources, including:
1. A nationally distributed NWIS field form that
inserted a user rounding code of '4' for many field parameters.
2. A bug in the code that inserted a ‘user
rounding code’ of '3' instead of referencing the parameter code dictionary.
The repair is limited
to 'field' data and does not address problems in rounding codes for analytical
results. The parameter code dictionary
is the source for the modifications, so the approach to this repair assumes
that one rounding array will work for each constituent. Generally, the parameter codes addressed in
the script are:
1. Fixed value parameter codes
2. Field parameters (typically have a reporting order number less
than 60)
3. Bacteria parameters
4. Field alkalinity and ANC parameters
5. Sediment concentration parameters
Detailed instructions for applying this update are located at:
http://ok.water.usgs.gov/nawqa/phoenix/rnd/upt_resultrnd.html
Questions can be
emailed to phoenix@usgs.gov.
Stephen
K. Sorenson
Acting
Chief, Office of Water Quality
This memorandum does
not supersede any other Office of Water Quality Technical Memorandum.
Distribution: All WRD Employees
Stephen K. Sorenson
Acting Chief, Office of Water Quality
US Geological Survey
412 National Center
Reston, Virginia 20192
703/648-6864
sorenson@usgs.gov