(Flags)=
# QA Flags



## How do flags work

@voc@ uses the boolean logic to combine flags. 
This means that each value is assigned one flag value.
The flag value can contain one or more flags.

If the value is 0, no flag is assigned.
If the value is 1, the flag with value 1 is assigned.
If the value is 2, the flag with value 2 is assigned.
If the value is 3, the flag with value 1 and 2 is assigned.

This allow to combine flags without having to create more variables.

[Learn more ](https://docs.python.org/3/library/enum.html#flag) 


## Descriptions

Various flags are available in @voc@. 

### Missing
QA_Flag.MISSING: 1

Missing value

### Zero neg conc ext
QA_Flag.ZERO_NEG_CONC_EXT: 2

A value of 0 or negative was calculated by an external software, but the value is marked as valid

### Invalidated ext
QA_Flag.INVALIDATED_EXT: 4

invalidated before the qa tool

### Extreme value
QA_Flag.EXTREME_VALUE: 8

Extreme value detected

### Uncorrelated
QA_Flag.UNCORRELATED: 16

Uncorrelated expected compounds
The compounds is expected to be correlated with another one, but it is not

### Calibration
QA_Flag.CALIBRATION: 32

Calibration run

### Blank
QA_Flag.BLANK: 64

Blank run

### Height integration
QA_Flag.HEIGHT_INTEGRATION: 128

Height integration instead of area integration

### Pollution
QA_Flag.POLLUTION: 256

Pollution flag

### Met office baseline
QA_Flag.MET_OFFICE_BASELINE: 512

Baseline

### Below detection limit
QA_Flag.BELOW_DETECTION_LIMIT: 1024

Below detection limit

### Suspicious rt
QA_Flag.SUSPICIOUS_RT: 2048

Bad retention time values

### Invalid values
QA_Flag.INVALID_VALUES: 4096

Invalid Values

### Target measurement
QA_Flag.TARGET_MEASUREMENT: 8192

Target measurement

### Laboratory standard
QA_Flag.LABORATORY_STANDARD: 16384

Laboratory standard

### Working standard
QA_Flag.WORKING_STANDARD: 32768

Working standard