QPR ProcessAnalyzer Expressions

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QPR ProcessAnalyzer Expressions

Expression and Evaluation Context

An expression is a representation of a piece of text to be evaluated that has a result. Result can be any of the supported object types or empty. An expression may consist of multiple expressions (sub-expressions).

Expression evaluation is always performed within some context. This context and its type defines which kind of functionalities are available. Current context is implicitly accessible in all the expressions. Whenever a function or property is called, functions and properties accessible in the current context are searched first. If function or property is not found in the current context, then more generic context is tried. Error is returned only if the requested functionality is not available in the current context or a generic context. Current context can always be accessed explicitly by using variable named: _ (underscore).

Expression Chaining and Hierarchies

Expressions can be chained together using . (dot) or : (colon) character between the expressions:

  • Contextless chaining: When . character is used to chain expressions together, only the result of the latter evaluation will be returned.
  • Hierarchical chaining: When : character is used to chain expressions together, only the result of the whole chained expression will consist of hierarchical arrays where all the values in the first expression will be bound to the arrays those values generated. If the second expression does not return an array, the result will be changed to be an array.

The second expression chained to the first one will be evaluated using the following rules:

  • If the result of the first expression is not an array, the second expression will be evaluated with the result of the first expression as its context object.
  • If the result of the first expression is an array, for every element in the array, the second expression will be evaluated with the array element as its context object. The result of the evaluation will be an array of evaluation results. One for each element in the array.
  • If any of the second expression evaluations returns an array, the resulting object will be an array of arrays. If the first expression evaluation returns a typed array, the result will be hierarchic in a way that first level results are objects that contain the information about the actual object as well as the results generated by the second level expressions.

These rules apply also when chaining more than two expressions together. For example, it is possible to generate three level hierarchy with nodes of type: event log -> case -> event: EventLogById(1).Cases.Events or EventLogById(1):Cases:Events.

Examples:

[1,2].("" + _ + "*foo").([_+"bar", _+"bob"])
Returns:
[["1*foobar","1*foobob"], ["2*foobar","2*foobob"]]

[1,2].("" + _ + "*foo"):([_+"bar", _+"bob"])
Returns:
[HierarchicalArray("1*foo", ["1*foobar","1*foobob"]), HierarchicalArray("2*foo", ["2*foobar","2*foobob"])]

[1,2]:("" + _ + "*foo"):([_+"bar", _+"bob"])
Returns:
[
HierarchicalArray(1, [
  HierarchicalArray("1*foo", ["1*foobar","1*foobob"])
]), 
HierarchicalArray(2, [
  HierarchicalArray("2*foo", ["2*foobar","2*foobob"])
])
]

GetValueOfContext("bar", ["foo":1, "bar":2])
Returns:
[2]
  • Hierarchical arrays: Whenever traversing 1-to-N cardinality relation in expression language that starts from a ProcessAnalyzer object (such as Case), a hierarchical array will be returned. Hierarchical array is an object which behaves just like a normal array except it stores also context/root/key/label object which usually represents the object from which the array originated from (e.g., the original case object when querying events of a case), or a key using which the actual value needs to be accessed by.
  • Hierarchical objects: Arrays where at least one object in the array is itself an array is considered to be a hierarchical object. Also known as multi dimensional arrays or array of arrays. Hierarchical arrays are treated in similar way as normal arrays in hierarchical objects.

Leaf, Depth, Level

Leaf level consists of all the nodes which are at depth equal to the depth of the whole hierarchical object.

Examples:

Objects at leaf level for hierarchical object: [[[3, 4, 5], 6], [1, 2]] are: 
Level 5: 3, 4, 5

Objects at leaf level for hierarchical object: [[1, 2], [[3, 4, 5], 6]] are: 
Level 4: 1, 2, [3, 4, 5], 6

Depth of a hierarchical object is the number of arrays that need to be traversed before a leaf node is found when traversing using depth first search using always the first object in each traversed array. Depth of the hierarchical object is not necessarily the maximum depth that could be achieved when traversing from object root to leaves. See the example below:

Examples:

Depth of hierarchical object [[1, 2], [[3, 4, 5], 6]] is: 2

NOTE!: 
Depth of hierarchical object [[[3, 4, 5], 6], [1, 2]] is: 3

Level in hierarchical object consists of all the nodes that are at specific depth in object's internal array hierarchy. 0 is the level at the root of the object (consisting only of the object itself as single item). Levels increase when moving towards leaves.

Examples:

Objects levels in hierarchical object: [[[3, 4, 5], 6], [1, 2]] are: 
Level 0: [[[3, 4, 5], 6], [1, 2]]
Level 1: [[3, 4, 5], 6], [1, 2]
Level 2: [3, 4, 5], 6, 1, 2
Level 3: 3, 4, 5 (Leaf Level)

Objects at leaf level for hierarchical object: [[1, 2], [[3, 4, 5], 6]] are: 
Level 0: [[1, 2], [[3, 4, 5], 6]]
Level 1: [1, 2], [[3, 4, 5], 6]
Level 2: 1, 2, [3, 4, 5], 6 (= Leaf Level #29303#)
Level 3: 3, 4, 5

Scopes

Scope defines the region of a expression where a specific variable or function name-value binding is valid. In expressions, a variable or function is valid in the following scopes:

  • Scope the variable or function was created.
  • All the child scopes created from the scope in which the variable or function was created.

A new scope is created based on the previous one in the following cases:

  • When starting to evaluate a expression.
  • When recursing the chain of expressions and the type of the current calculation context object is not the same as the previously used one.
  • When evaluating user defined function and its parameters.
  • When evaluating KPI analysis dimensions.
  • When evaluating KPI analysis column names in dynamic values.

User Defined Variables

Variables are properties originating from the current variable scope. Variables can be defined by user into the current scope using Let function. Variables defined in parent scope are available also in all the child scopes. Variables can't be used to override properties. Properties are always checked first before checking scope for variables. For example, you can't override Models property by specifying Models variable.

Aggregation Functions

When using aggregation functions (such as Count, Sum, ...) or functions that modify the contents of leaf arrays (OrderBy, Distinct, ...) on hierarchical objects, the operations will be performed by default separately for every array at level that equals to the depth of the object (leaf level) or some specific number of levels up from that.

There are following aggregation functions available: Average, Count, Min, Max and Sum.

Examples:

Count([[1, 2], [3, 4]])
Returns: [2, 2]

OrderByValue([[4, 3], [2, 1]])
Returns: [[3, 4], [1, 2]]

NOTE:
OrderByValue([[4, 3], [2, 1], [[6, 5]]])
Returns: [[3, 4], [1, 2], [[6, 5]]]

Type Independent Properties and Functions

Type Independent Property Description
_
_empty
_remove
CalcId (string)
Models (Model*) Models in the QPR ProcessAnalyzer server.
Now (DateTime) Timestamp of representing the current date and time.
Null
Projects (Project*) Projects in the QPR ProcessAnalyzer server.
Type Independent Function Parameters Description
Ceiling
Floor
Round
Array
DateTime
TimeSpan
Box
Unbox
Catch
Coalesce
Def
Distinct
EventLogById
ModelById
FindRepeats
Repeat
Flatten
For
ForEach
GetAt
GetAtReverse
GetValueOfContext
If
In
Include
IsNull
Let
OrderBy
OrderByDescending
OrderByValue
OrderByValueDescending
RemoveLeaves
ReplaceLeafValues
SliceMiddle
StopOnNull
StringJoin
TimeRange
Variable
Where

Properties and Functions by Object Types

Arrays

Array functions Parameters Description
IndexOfSubArray (integer)
  • Sub-array to search(array)
  • Array from where to search the sub-array (array)
Returns the indexes of given sub-array (1. parameter) within the given array (2. parameter). If not given, the array in the current context object is used. Returns starting indexes of all the occurrences of given sub-array within given array.

Examples:

[[1,2,3,4,1,2,5]].IndexOfSubArray([1,2])
IndexOfSubArray([1,2], [1,2,3,4,1,2,5])
Return: [0, 4]

[[1,2,3,4,1,2,5]].IndexOfSubArray([1,2,3,4,5])
Returns: []

[[1,2,3,4,1,2,5],[3,4],[0,1,2,3]]:IndexOfSubArray([1,2])
Returns:
[
  HierarchicalArray([1,2,3,4,1,2,5], [0,4]),
  HierarchicalArray([0,1,2,3], [1])
]

AttributeType

Case properties Description
Id (Integer) AttributeType Id.
Name (String) Attribute name.

Case

Case properties Description
Duration (TimeSpan) Case duration, i.e. duration between case start and case end time.
EndTime (DateTime) Case end time, i.e. timestamp of the last event.
Events (Event) All events of the case.
FlowOccurrences (FlowOccurrency) All flow occurrences the case contains.
Flows (Flow) All flows the case goes through.
Id (String) Case Id.
Name (String) Case name
StartTime (DateTime) Case start time, i.e. timestamp of the first event.
Variation (Variation) Variation the case belongs to.
Case functions Parameters Description
Attribute (Object)
  • attribute name (string)
Case attribute value. Case attribute name is provided as a parameter.

Event

Event properties Description
Case (Case) Case the event belongs to.
Id (Integer) Event id.
IndexInCase (Integer) Index (running) number of the event in the case (ordered temporally). The first event has index number 0.
Model (Model) Model the event belongs to.
NextInCase (Event) Temporally next event in the case. For the last event, return EMPTY.
PreviousInCase (Event) Temporally previous event in the case. For the first event, return EMPTY.
TimeStamp (DateTime) Timestamp of the event.
Type (EvenType) Event type of the event.

For future: OutgoingFlow, IncomingFlow, OutgoingFlowOccurrence, IncomingFlowOccurrence, Variations

Event functions Parameters Description
Attribute (object)
  • attribute name (string)
Event attribute value. Event attribute name is provided as a parameter.

EventLog

Event properties Description
CaseAttributes (AttributeType*) Used case attribute in the EventLog.
Cases (Case*) Cases that belong to the EventLog.
EventAttributes (AttributeType*) Used event attributes in the EventLog.
Events (Event*) Events that belong to the EventLog.
EventTypes (EventType*) EventTypes in the EventLog.
Flows (Flow*) Flows that the part of the EventLog.
Id EventLog Id.
Model (Model) Model where the EventLog belongs.
Name EventLog name.
Variations (Variation*) Variations that are in the EventLog

EventType

EventType properties Description
Cases (Case*) Cases that contain the EventType.
Count (Integer) Event count that have this EventType.
Events (Event*) Events of that EventType.
Id (Integer) EventType Id.
Name (string) EventType name.

For future: OutgoingFlow, IncomingFlow, Variations

Flow

Flow is a combination of two EventTypes where there are FlowOccurrences between them. Unlike FlowOccurrencies, a Flow is not related to a single case. Flowchart shows Flows and EventTypes (not FlowOccurences or Events). In a Case, the may be several FlowOccurrences of a single Flow.

Variation properties Description
Cases (Case*) Cases that contain the flow, i.e. there is a flow occurrence between Flow's starting and ending events.
FlowOccurrences (FlowOccurrence*) Flow occurrences the flow belongs to.
Id (Integer) Flow Id.
Name (string) Identifying name of the Flow.

For future: FromEventType, ToEventType

FlowOccurrence

FlowOccurrence represents a transition from an event to another event in a case. Thus, FlowOccurrence is related to a single case. There is also a FlowOccurrence from the "start" of the case to the first event of the case, and a FlowOccurrence from the last event of the case to the "end" of the case. Corresponding flow is visible in BPMN kind of flowcharts showing separate start and event icons. Thus, there are one more FlowOccurrences in a case than the number of events.

Variation properties Description
Case (Case) Case the FlowOccurrence belongs to.
Flow (Flow) Corresponding Flow of the FlowOccurrence.
Id (Integer) FlowOccurrence Id.
Name (String) Identifying name of the FlowOccurrence.
OccurrenceIndex (Integer) Number tells how many times the FlowOccurrence has occurred in the case until that point.

For future: FromEvent, ToEvent, Duration

TimeSpan

TimeSpan represents a temporal duration (for example: 5 hours or 8 days). TimeSpan is not bound to calendar time. Difference between two TimeStamps is TimeSpan. TimeStamp added by TimeSpan is TimeStamp.

TimeSpan properties Description
TotalDays (Float) Timespan value in days (one day is 24 hours) (both whole and fractional).
TotalHours (Float) Timespan value in hours (both whole and fractional).
TotalMilliseconds (Float) Timespan value in milliseconds(both whole and fractional).
TotalMinutes (Float) Timespan value in minutes (both whole and fractional).
TotalSeconds (Float) Timespan value in seconds (both whole and fractional).

Variation

Variation properties Description
CaseCount (Integer) Number of cases in the variation.
Cases (Case*) Cases that belong to the variation.
EventTypeCount (Integer) Number of events in the variation.
EventTypes (EventType*) Event types belonging to the variation.
Id (Integer) Variation Id.
UniqueEventTypeCount (Integer) Number of different (unique) event types in the variation.

DateTime

Properties: Day, Hour, Millisecond, Minute, Month, Second, Year