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This option will, as it says, fill in data gaps with 'NaN' values in the data products. For CSV files, the text 'NaN' is inserted, while MAT files have a built-in type of the same name. Data gaps occur when the time difference between subsequent readings is greater than 1.9 times the sample period (otherwise known as the data rating). The NaNs are placed one sample period after the last reading before the data gaps. Gaps are only filled between readings.
This option will also keep any existing NaNs in the data. These are most often caused by the clean data option being selected, or by real NaNs being report, or when a sensor in a multi-sensor data product has no data. The metadata report accompanying the data product will Available metadata can elaborate on the QAQC test that was applied (this information is available via Oceans 3.0 and in MAT files).
This is the default option.
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