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About Decoding QC Test Codes Sorted by the Stage Numbers

The GTSPP Quality Control (QC) test codes and results are stored in a eight-byte hexadecimal number, which can represent up-to 32 different tests and the test results. Each byte of the hexadecimal number has four (4) bits. A bit represents either 1 (one: test performed or failed) or 0 (zero: test not performed or passed) only.

The steps of interpretion of GTSPP QC test codes and results are as follows:

  1. Convert the QC test codes ( or results) from hexadecimal to decimal number.
  2. Convert the decimal number to binary number.
  3. Reverse the binary number in accordance with the order of the GTSPP QC test numbers.
  4. Map the reversed bit numbers to the cooresponding numbers of the QC tests in the ascending order and identify the test names and results, accordingly.
For example, the following table is a sample list of data quality control tests code (QCP$=41E1FFD) and results (QCF$=0000004) performed by the Integrated Scientific Data Management in Canada. The table indicates:
  1. The first test, 'Platform Identification Test", was performed (1=Y) and the test result showed "Passed" (0=P)
  2. The second test, "Impossible Date/Time", was not performed (0=N).
  3. The third test, "Impossible Location", was performed (1=Y) and passed (0=P).
  4. and so on...
Stage Number Test Number Index Number Test Name QCP$ =41E1FFD (0=OFF/1=ON) QCF$=0000004 (0=P/1=F)
Stage 1: Location and Identification Tests
1.1 1 1 Platform Identification 1 0
1.2 2 2 Impossible Date/Time 0 0
1.3 3 4 Impossible Location 1 0
1.4 4 8 Position on Land 1 0
1.5 5 16 Impossible Speed 1 0
1.6 6 32 Impossible Sounding 0 0
Stage 2: Profile Tests
2.1 7 64 Global Impossible Parameter Values 1 1
2.2 8 128 Regional Impossible Parameter Values 0 0
2.3 9 256 Increasing Depth 1 0
2.4 10 512 Profile Envelop 1 1
2.5 11 1024 Constant Profil 0 0
2.6 12 2048 Freezing Point 0 0
2.7 13 4096 Spike 1 1
2.8 14 8192 Top and Bottom Spike 1 0
2.9 15 16384 Gradien 1 1
2.10 16 32768 Density Inversion 0 0
2.11 24 8388608 Bottom 0 0
2.12 25 16777216 Temperature Inversion 0 0
Stage 3: Climatology Tests
3.1 17 65536 Levitus Seasonal Statistics 1 1
3.2 18 131072 Emery and Dewar Climatology 0 0
3.3 19 262144 Asheville Climatology 0 0
3.4 20 524288 Levitus Monthly Climatology 0 0
3.5 26 33554432 Levitus Annual Climatology 0 0
Stage 4: Profile Consistency Tests
4.1 21 1048576 Waterfall 0 0
Stage 5: Visual Inspection
5.1 22 2097152 Cruise Track 1 0
5.2 23 4194304 Profiles 0 0

The list of data quality control test codes and results sorted by the test numbers is available here.