What | Required | Description | schema location |
---|---|---|---|
ValidationRulesets.xml | no | Definition of validation rule sets | http://fews.wldelft.nl/schemas/version1.0/validationRuleSets.xsd |
Validation rules are defined in DELFT-FEWS to allow quality checking of all time series data (scalar time series only). Several validation criteria may be defined per time series. All validation rules for all time series are defined in this configuration. For each time series to be checked, a set of validation rules is defined. Defining validation rules to apply to a time series set using a locationSet rather than identifying series individually can simplify the configuration greatly. Most validation rules may be defined either as a constant value, or as a value valid per calendar month.
When available on the file system, the name of the XML file for configuring the Validation Rule Sets is for example:
ValidationRuleSets 1.00 default.xml
ValidationRuleSets Fixed file name for the Validation rules configuration
1.00 Version number
default Flag to indicate the version is the default configuration (otherwise omitted).
Figure 33 Elements of the ValidationRuleSets configuration.
validationRuleSet
Root element of the definition of a validation rule set. Multiple entries may exist.
Attributes;
- validationRuleSetId: Optional reference ID for the validation rule set. Used only in messaging.
- timeZone: Shift (in hours) of the time zone to be used in considering time values in validation.
considerQualifiers
When matching timeSeriesSets during primary validation qualifiers are per default not considered. But by adding a <considerQualifiers> element to the validationRuleSet and setting it to true, the qualifiers also have to match for the validationRuleSet to match.
logLevel
Optional log level for the log message that is logged if a time series violates a rule in this validationRuleSet. Can be WARN, INFO or DEBUG. Default is WARN.
unit
Specify when the unit given for the values is not the same as the (internally stored) unit of the parameter it applies to. When specified it is required to also specify configUnitConversionsId in Parameters.xml. The conversion from the specified unit to the (internal) unit should be available in the unit conversions config file.
timeSeriesSet
Definition of the time series to apply validation rule to.
extremeValues
Validation rules defined to check for extreme values (hard and soft limits)
rateOfChange
Validation rules defined to check rate of change. Please note the units are per second i.e. 2m in 15mins is 0.00222.
sameReading
Validation rules defined to check for series of same readings.
temporaryShift
Validation rules defined to check for temporary shifts in time series.
extremeValuesFunctions, rateOfChangeFunctions, sameReadingFunctions, temporaryShiftFunctions
These function have to do with Shape-DBF file configuration. See here
Location dependency
For extremeValues, rateOfChange, sameReading and temporaryShift a locationId can be given to make the rule location specific. Before 2014.02 this functionality was used to make multiple location-specific rules of the same type within a single validationRuleSet.
From 2014.02 on multiple rules of the same type within a single validationRuleSet can be given to apply to all locations within the timeSeriesSet instead of them to be location specific. Also from 2014.02 on multiple rateOfChangeFunctions, sameReadingFunctions and temporaryShiftFunctions can be used within the same validation rule set.
Validation on extreme values
This group of validation rules checks that the values in the time series do not exceed minimum and maximum limits. These limits may be defined as soft limits or as hard limits. Values exceeding soft limits will be marked as doubtful but retained. Values exceeding hard limits will be marked as unreliable.
Figure 34 Elements of the Extreme values configuration of the ValidationRuleSets.
hardMax
Validation rule for checking hard maximum. Values exceeding this limit will be marked as unreliable.
Attributes;
- constantValue: Value of hardMax limit, used irrespective of time of value.
hardMin
Validation rule for checking hard minimum. Values exceeding this limit will be marked as unreliable.
Attributes;
- constantValue: Value of hardMin limit, used irrespective of time of value.
softMax
Validation rule for checking soft maximum. Values exceeding this limit will be marked as doubtful.
Attributes;
- constantValue: Value of softMax limit, used irrespective of time of value.
softMin
Validation rule for checking soft minimum. Values exceeding this limit will be marked as doubtful.
Attributes;
- constantValue: Value of softMin limit, used irrespective of time of value.
monthLimit
Element used when defining variable limits per calendar month. Twelve values must be defined. When defined the monthly limit will overrule the constant limit.
Validation on rate of change
This group of validation rules checks that the values in the time series do not exceed maximum rates of change. When the rate of change limit is exceeded, the values causing the limit to be exceeded will be marked as unreliable. Rate of change limits may be defined to be the same for the rate of rise as for the rate of fall. These may also be defined to be different. The rates need to be specified in the unit of the timeseries it applies per second. E.g. if you define a rate of change for a water level gauge with values in metres the rate should be given in metres per second.
Figure 35 Elements of the rate of change configuration of the ValidationRuleSets.
rateofRiseFallDifferent
Root element used if the rate of rise limit is defined different to the rate of fall.
rateOfRise
Validation rule defined for the rate of rise.
Attributes;
- constantValue: Maximum rate of rise, used irrespective of date of the value. []
rateOfFall
Validation rule defined for the rate of fall.
Attributes;
- constantValue: Maximum rate of fall, used irrespective of date of the value. []
monthLimit
Element used when defining variable limits per calendar month. Twelve values must be defined. When defined the monthly limit will overrule the constant limit.
Validation on series of same readings
Time series of data can be validated on series of same readings. This may be unlikely for field observations, and may indicate an instrumental error. In some cases a small variability may still be observed, despite instrumental error. The same readings check allows for defining a bandwidth within the value is considered to be the same.
Figure 36 Elements of the same reading configuration of the ValidationRuleSets.
SameReadingViolations are marked as such if values stay within the sameReadingDeviation for at least the sameReadingPeriod. The way the check is applied is by having each value in the timeSeries be considered as potential start of a period in which the reading will be the same.
For each non missing value (start value) a check on the timeSeries is applied as follows. After the start value, each non missing value is compared to the start value to see if the absolute difference is no more than the sameReadingDeviation. If it's equal to or less than the sameReadingDeviation, the value is considered to be within the bandwidth and the check is continued. If not (or if it was the last non missing value of the timeSeries), the check is stopped. If the time between the start value and the last value inside the bandwidth is equal to or greater than the sameReadingPeriod, all non missing values from the start value up to (and including) the last value are marked sameReading (SR).
After this, the check is applied to the first non missing value after, what was considered in the last check as, starting value (even if it is already marked as sameReading).
sameReadingDeviation
Root element for definition of bandwidth the value may vary within if it is considered to the same reading. The bandwidth is twice the deviation.
Attributes;
- constantValue: Value for deviation (inclusive), used irrespective of date of the value.
sameReadingPeriod
Root element for definition of time span limit the value may remain the same to be considered realistic. If the reading remains the same for a longer period of time, ensuing values will be considered unreliable.
Attributes;
- constantValue: Value for time span in seconds (exclusive), used irrespective of date of the value.
monthLimit
Element used when defining variable limits per calendar month. Twelve values must be defined. When defined the monthly limit will overrule the constant limit.
Validation on Temporary Shifts
Time series of data can be validated on temporary shifts. These occur when instruments are reset, and can be identified by the values rapidly falling to a constant value, remaining at that value for a short period of time and then returning to the original value range. A complex set of validation criteria include the rate of change as well as a maximum time the value remains the same.
Figure 37 Elements of the temporary shift configuration of the ValidationRuleSets.
rateOfTemporaryShift
Rate of change that must be exceeded both on change to shifted value and change back to original value range for validation rule to apply.
Attributes;
- constantValue: Value for rate of change, used irrespective of date of the value.
temporaryShiftPeriod
Maximum time span constant shifted value is in time series for validation rule to apply.
Attributes;
- constantValue: Value for time span in seconds, used irrespective of date of the value.
monthLimit
Element used when defining variable limits per calendar month. Twelve values must be defined. When defined the monthly limit will overrule the constant limit.
flagSources
Since version 2012.01 FEWS stores not only the quality flags, but also the source of the flag, the so-called flagSource. So the user is able to see why a certain value is validated as unreliable, eg. due to exceeding of the hard max.
The list of flagSources is:
- IMP: flag is imported
- SN: soft min.
- HN: hard min.
- SX: soft max.
- HX: hard max.
- ROR: rate of rise
- ROF: rate of fall
- SR: same reading
- TS: temporary shift
- SC: secundairy validation, series comparison
- FC: secundairy validation, flag comparison
- KT: secundairy validation, Mann-Kendall test
- MAN: manual edit
Example for "Rate of Rise" and "Temporary Shift" validation rules
Examples of validation rules
Example for "Rate of Rise" and "Temporary Shift" validation rules