Panini
Language Dictionary
How to Read this Dictionary
This dictionary identifies the keywords used in the Panini analytic domain specific language. Each keyword is identified with its type. There are 3 distinct types: bound attribute, metadata, and workflow hook.
bound attribute |
The keyword’s value or the source of its value is derived from analytic context and bound during the binding step of the DSL workflow |
metadata |
The keyword’s value provides information about the analytic definition itself |
workflow hook |
The keyword provides the definition creator with a hook into the DSL workflow for use during the execution of the analytic function. |
In addition to type, each keyword definition also includes a description, list of parameters accepted by the keyword, an example showing how it is declared in an analytic definition and one or more examples of how it is used in the analytic function.
Entries
alert, bufferedInput, constant, definition, description, input, multivariate, onBind, onCalculate, onInput, onTimerEvent, output, ownerId, version
alert
alert – bound attribute
Declare an alert parameter which can be used in the analytic function to raise an FX5 alert based on the results of the analytic calculation.
parameters:
name required A name that will be used to identify the bound alert within the analytic function
description optional A description of the alert and its use within the analytic function
declaration:
alert name:'limitExceeded', description:'a description of the alert'
usage:
create an alert
createAlert 'limitExceeded'
clear an alert
clearAlert 'limitExceeded'
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buffered-Input
bufferedInput – bound attribute
Declare an input parameter that buffers (or accumulates) values over time. Once bound, a bufferedInput parameter will buffer up to 500 values before new values replace to oldest in the buffer. When values are used, they are removed from the buffer.
parameters:
name required A name that will be used to identify the bound bufferedInput value within the analytic function
type optional The type of the bufferedInput value - one of: integer, long, float, double, boolean
description optional A description of the bufferedInputs use within the analytic function
initialbufferingstate optional True or False, begin buffering input values upon start of an analytic block. Defaults to True
declaration:
bufferedInput name:'source', type:'long', description:'a description of the source buffered input', initialbufferingstate:false
usage:
access all the values in the buffer
def values = bufferedInput.useValues 'source'
access a subset of the values in the buffer by providing a filter function
def values = bufferedInput.useValues 'source', { v -> v.getUpdateTimeMillis() < endTime }
turn off buffering for a bufferedInput attribute
bufferedInput.stopBuffering 'source'
turn on buffering for a bufferedInput attribute
bufferedInput.startBuffering 'source'
get the timestamp for the most recent value in the buffer
bufferedInput.getMostRecentTimestamp 'source'
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constant
constant – bound attribute
Declare constant value that will be provided by the context once bound.
parameters:
name required A name that will be used to identify the bound constant within the analytic function
type optional The type of the constant value - one of: integer, long, float, double, boolean
description optional A description of the constants use within the analytic function
declaration:
constant name:'rate', type:'long', description:'a description for the rate constant'
usage:
access the bound constant value
constant.get 'rate'
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definition
definition – metadata
Provide a name for the analytic block definition.
declaration:
definition 'Derivative'
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description
description – metadata
Provide a description of the analytic block definition.
declaration:
description 'Function that calculates the rate of change for an input'
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input
input – bound attribute
Declare an input parameter that will provide a stream of data to the analytic function once bound.
parameters:
name required A name that will be used to identify the bound input value within the analytic function
type optional The type of the input value - one of: integer, long, float, double, boolean
description optional A description of the inputs use within the analytic function
declaration:
input name:'monitor', type:'double', description:'a description of the monitor input'
usage:
access the latest value of the entity bound to the declared input
input.get 'monitor'
access the timestamp of the latest value of the entity bound to the declared input as provided by the input source
input.getTimestamp 'monitor'
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multivariate
multivariate – bound attribute
Declare a multivariate set of inputs and the expression to evaluate them.
parameters:
description optional A description of the multivariate function
declaration:
multivariate description:'a description of the multivariate function'
usage:
multivariate is for internal use only
an analytic block definition can have only one multivariate defined
determine whether or not the multivariate is ready for execution i.e. has a value from all bound input sources
if( multivariate.ready() ) ...
evaluate the multivariate expression and set the result for publishing
setOutputValue 'result', evalExpression( multivariate.expression() ), System.currentTimeMillis()
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on-Bind
onBind – workflow hook
Optional – Declare a block that will be executed as the last step in binding a context to an analytic definition creating an executable analytic block
declaration:
onBind {
...
}
usage:
onBind is typically used to initialize local variables and constants with default values in the event that the bound context doesn’t provide a binding
onBind {
sampleThreshold = constant.get 'sampleThreshold' ?: DFLT_THRESHOLD
rateMillis = constant.get 'rateMillis' ?: DFLT_RATE
sampleCount = 0
lastReading = 0.0
lastReadingTimestamp = 0
}
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on-Calculate
onCalculate – workflow hook
Optional – Declare a block that will be executed when the implementing engine determines that the analytic block should execute. This will typically be every time a bound input value is updated.
declaration:
onCalculate {
...
}
usage:
onCalculate is used to define an analytic function that will be executed at the discretion of the implementing engine, typically every time an input value changes. For more control see: onInput and onTimerEvent
onCalculate {
long currTimeMillis = System.currentTimeMillis()
if( multivariate.ready() ) {
setOutputValue 'result', evalExpression( multivariate.expression() ), currTimeMillis
}
}
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on-Input
onInput – workflow hook
Optional – Declare a block that will be executed every time the analytic block receives an update to the declared input binding
declaration:
onInput 'source', {
...
}
usage:
Use onInput when there is a need to run a block any time a bound input receives an update. It is possible to have multiple onInput declarations, up to one for each defined input attribute.
onInput ‘trigger’, {
boolean buffer = input.get ‘trigger’
long triggerTimestamp = input.getTimestamp ‘trigger’
if( buffer ) bufferedInput.startBuffering ‘source’
else {
...
}
...
}
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on-Timer-Event
onTimerEvent – workflow hook
Optional – Declare a block that will be executed every time a time event is received. Timer events typically have a 1 second resolution but be sure to understand the execution environment to ensure calculations are triggered at the desired time interval.
declaration:
onTimerEvent {
...
}
usage:
onTimerEvent is used to declare blocks that need to be executed at regular time intervals.
onTimerEvent {
currTime = System.currentTimeMillis()
if( currTime >= endTime ) {
def min = MAX, max = MIN
def vals = bufferedInput.useValues 'source', { v -> v.getUpdateTimeMillis() < endTime }
...
}
...
}
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output
output – bound attribute
Declare an output parameter that is used to publish analytic results to the bound channel.
parameters:
name required A name that will be used to identify the bound output channel within the analytic function
type optional The type of the value that will be published on the bound channel - one of: integer, long, float, double, boolean
description optional A description of the output for the analytic function
outputonchangeonly optional True or False, publish the calculated value only if it has changed. Defaults to Falsedeclaration:
output name:'min', type:'integer', description:'a description for the min output parameter', outputonchangeonly:true
usage:
set an output value with the current timestamp
setOutputValue 'min', 33
set an output value with a timestamp other than current, usually a timestamp from an input parameter that triggered the calculation
setOutputValue 'min', 33, timestamp
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