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Curve Configuration & ODSL Syntax

Smart Curves are defined using ODSL — the OpenDataDSL domain-specific language. A curve definition specifies the inputs, the build method, and the output structure. This page walks through how to configure a Smart Curve from scratch.

Basic Structure​

A Smart Curve is always stored as a property on a master data object. The SmartCurve() constructor takes two arguments — the base data reference and the build expression — and the result is saved via the object service.

// Create or reference the master data object
MY_OBJECT = Object()

// Define the Smart Curve: SmartCurve(baseDataRef, expression)
sc = SmartCurve("MY_EXCHANGE.GAS_FRONT_MONTH:CLOSE", "BASE")

// Attach to the master data object and save
MY_OBJECT.CURVE = sc
save ${object:MY_OBJECT}

Key Concepts​

ConceptDescription
Base data referenceThe primary input curve, passed as the first argument to SmartCurve() — referenced as BASE in the expression
ExpressionA string defining the build logic, using BASE for the primary input and named variables for additional inputs
Named variablesAdditional input curves, added as properties on the SmartCurve and referenced by name in the expression
Master data objectThe Smart Curve is stored as a property on an object and saved via ${object:...}
tip

BASE always refers to the first argument passed to SmartCurve(). Additional inputs are defined as named variables on the SmartCurve and referenced by their property name in the expression.

Adding Named Variable Inputs​

When your expression needs more than one input, define additional curves as named properties using ref():

MY_OBJECT = Object()

sc = SmartCurve("SOURCE_A.CURVE:PRICE", "BASE-VAR1")
sc.VAR1 = ref("data", "SOURCE_B.CURVE:PRICE")

MY_OBJECT.CURVE = sc
save ${object:MY_OBJECT}

Here BASE is the primary input (SOURCE_A) and VAR1 is the second input (SOURCE_B). The expression BASE-VAR1 computes the spread between them.

note

You can define as many named variables as your expression requires. Each is added as a property on the SmartCurve using ref("data", "OBJECT_ID:PROPERTY").

Bootstrapping Configuration​

To bootstrap a curve, use bootstrapCurve(BASE) as the expression. The base data reference is the primary contract series passed into SmartCurve():

GAS_OBJECT = Object()

sc = SmartCurve("ICE.NBP_M:SETTLE", "bootstrapCurve(BASE)")

GAS_OBJECT.CURVE = sc
save ${object:GAS_OBJECT}

To bootstrap from multiple contract tenors, add the additional series as named variables:

GAS_OBJECT = Object()

sc = SmartCurve("ICE.NBP_M:SETTLE", "bootstrapCurve(BASE, VAR1)")
sc.VAR1 = ref("data", "ICE.NBP_Q:SETTLE")

GAS_OBJECT.CURVE = sc
save ${object:GAS_OBJECT}
note

When multiple contract tenors are provided, the bootstrapper resolves overlaps automatically, preferring the most granular (shortest tenor) instrument.

Interpolation Configuration​

Wrap the expression with interpolate() to produce a smoother or higher-granularity output curve:

DAILY_OBJECT = Object()

sc = SmartCurve("MY_EXCHANGE.CURVE:PRICE", "interpolate(BASE, 'cubicspline', 'daily')")

DAILY_OBJECT.CURVE = sc
save ${object:DAILY_OBJECT}

Supported interpolation methods:

ValueDescription
linearStraight-line between points
cubicsplineSmooth spline through all points
flatforwardHold previous value until next point

Blending Configuration​

Use named variables to define the curves to blend, then reference them in the expression:

BLENDED_OBJECT = Object()

sc = SmartCurve("ICE.NBP:SETTLE", "blendCurves(BASE, VAR1, 'priority')")
sc.VAR1 = ref("data", "BROKER.NBP:MID")

BLENDED_OBJECT.CURVE = sc
save ${object:BLENDED_OBJECT}

For weighted blending, supply weights in the expression:

sc = SmartCurve("SOURCE_A.CURVE:PRICE", "weightedBlend(BASE, 0.7, VAR1, 0.3)")
sc.VAR1 = ref("data", "SOURCE_B.CURVE:PRICE")

Spread Curve Configuration​

Spread curves use arithmetic expressions with BASE and named variables:

SPREAD_OBJECT = Object()

// Spark spread = power - (gas * heat rate)
sc = SmartCurve("EPEX.POWER_CAL:SETTLE", "BASE-(VAR1*0.45)")
sc.VAR1 = ref("data", "ICE.TTF_CAL:SETTLE")

SPREAD_OBJECT.SPARK_SPREAD = sc
save ${object:SPREAD_OBJECT}
tip

ODSL supports standard arithmetic operators (+, -, *, /) directly in Smart Curve expressions, making spread and ratio curves straightforward to define.

Seasonal Shape Configuration​

Apply a seasonal shape to a base curve using a named variable for the shape input:

SHAPED_OBJECT = Object()

sc = SmartCurve("MY_EXCHANGE.BASE_CURVE:PRICE", "applyShape(BASE, VAR1, 'multiplicative')")
sc.VAR1 = ref("data", "MY_COMPANY.SEASONAL_SHAPE:FACTOR")

SHAPED_OBJECT.CURVE = sc
save ${object:SHAPED_OBJECT}

Full Example: Power Forward Curve​

Here is a complete example combining blending, bootstrapping, and interpolation using the correct SmartCurve pattern:

// Reference the master data object for EEX German power
POWER_OBJECT = Object()
POWER_OBJECT.description = "German Power Forward Curve - Daily"

// Step 1: blend EEX and broker (EEX = BASE, broker = VAR1)
// Step 2: bootstrap the blended result
// Step 3: interpolate to daily
sc = SmartCurve(
    "EEX.DE_POWER_M:SETTLE",
    "interpolate(bootstrapCurve(blendCurves(BASE, VAR1, 'priority')), 'cubicspline', 'daily')"
)
sc.VAR1 = ref("data", "BROKER.DE_POWER_M:MID")

POWER_OBJECT.CURVE = sc
save ${object:POWER_OBJECT}
tip

Expressions can be nested — interpolate(bootstrapCurve(...)) chains the two operations in a single expression string. Break complex expressions into readable lines using ODSL string concatenation if needed.

Next Steps​