Squants

The Scala API for Quantities, Units of Measure and Dimensional Analysis

Squants is a framework of data types and a domain specific language (DSL) for representing Quantities, their Units of Measure, and their Dimensional relationships. The API supports typesafe dimensional analysis, improved domain models and more. All types are immutable and thread-safe.

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Current Versions

Current Release: 0.5.3 (API Docs)

Development Build: 0.6.1-SNAPSHOT (API Docs)

Release History

Build services provided by Travis CI

NOTE - This README reflects feature set in the branch it can be found.
For more information on feature availability of a specific version see the Release History or the README for a that version

Installation

Repository hosting for Squants is provided by Sonatype. To use Squants in your SBT project add the following dependency to your build.

"com.squants" %% "squants" % "0.5.3"

or

"com.squants" %% "squants" % "0.6.1-SNAPSHOT"

To use Squants in your Maven project add the following dependency

<dependency>
<groupId>com.squants</groupId>
<artifactId>squants_2.11</artifactId>
<version>0.5.3</version>
</dependency>

Beginning with Squants 0.4.x series, both Scala 2.10 and 2.11 builds are available.

To use Squants interactively in the Scala REPL, clone the git repo and run sbt squantsJVM/console

git clone https://github.com/garyKeorkunian/squants
cd squants
sbt squantsJVM/console

Type Safe Dimensional Analysis

The Trouble with Doubles

When building programs that perform dimensional analysis, developers are quick to declare quantities using a basic numeric type, usually Double. While this may be satisfactory in some situations, it can often lead to semantic and other logic issues.

For example, when using a Double to describe quantities of Energy (kWh) and Power (kW), it is possible to compile a program that adds these two values together. This is not appropriate as kW and kWh measure quantities of two different dimensions. The unit kWh is used to measure an amount of Energy used or produced. The unit kW is used to measure Power/Load, the rate at which Energy is being used or produced, that is, Power is the first time derivative of Energy.

Power = Energy / Time

Consider the following code

valloadKw=1.2// Double: 1.2valenergyMwh=24.2// Double: 24.2 valsumKw= loadKw + energyMwh // Double: 25.4

which not only adds quantities of different dimensions (Power vs Energy), it also fails to convert the scales implied in the val names (Mega vs Kilo). Because this code compiles, detection of these errors is pushed further into the development cycle.

Dimensional Type Safety

Only quantities with the same dimensions may be compared, equated, added, or subtracted.

Squants helps prevent errors like these by type checking operations at compile time and automatically applying scale and type conversions at run-time. For example,

valload1:Power=Kilowatts(12) // returns Power(12, Kilowatts) or 12 kWvalload2:Power=Megawatts(0.023) // Power: 0.023 MWvalsum= load1 + load2 // Power: 35 kW - unit on left side is preserved
sum should be(Kilowatts(35)) sum should be(Megawatts(0.035)) // comparisons automatically convert scale 

works because Kilowatts and Megawatts are both units of Power. Only the scale is different and the library applies an appropriate conversion. Also, notice that keeping track of the scale within the value name is no longer needed.

valload:Power=Kilowatts(1.2) // Power: 1.2 kWvalenergy:Energy=KilowattHours(23.0) // Energy: 23 kWHvalsum= load + energy // Invalid operation - does not compile

The unsupported operation in this expression prevents the code from compiling, catching the error made when using Double in the example above.

Dimensionally Correct Type Conversions

One may take quantities with different dimensions, and multiply or divide them.

Dimensionally correct type conversions are a key feature of Squants. Conversions are implemented by defining relationships between Quantity types using the * and / operators.

The following code demonstrates creating ratio between two quantities of the same dimension, resulting in a dimensionless value:

valratio=Days(1) /Hours(3) // Double: 8.0

This code demonstrates use of the Power.* method that takes a Time and returns an Energy:

valload=Kilowatts(1.2) // Power: 1.2 kWvaltime=Hours(2) // Time: 2 hvalenergyUsed= load * time // Energy: 2.4 kWh

This code demonstrates use of the Energy./ method that takes a Time and returns a Power:

valaveLoad:Power= energyUsed / time // Power: 1.2 kW

Unit Conversions

Quantity values are based in the units used to create them.

valloadA:Power=Kilowatts(1200) // Power: 1200.0 kWvalloadB:Power=Megawatts(1200) // Power: 1200.0 MW

Since Squants properly equates values of a like dimension, regardless of the unit, there is usually no reason to explicitly convert from one to the other. This is especially true if the user code is primarily performing dimensional analysis.

However, there are times when you may need to set a Quantity value to a specific unit (eg, for proper JSON encoding).

When necessary, a quantity can be converted to another unit using the in method.

valloadA=Kilowatts(1200) // Power: 1200.0 kWvalloadB= loadA in Megawatts// Power: 1.2 MWvalloadC= loadA in Gigawatts// Power: 0.0012 GW

Sometimes you need to get the numeric value of the quantity in a specific unit (eg, for submission to an external service that requires a numeric in a specified unit or to perform analysis beyond Squant's domain)

When necessary, the value can be extracted in the desired unit with the to method.

valload:Power=Kilowatts(1200)
valkw:Double= load to Kilowatts// Double: 1200.0valmw:Double= load to Megawatts// Double: 1.2valgw:Double= load to Gigawatts// Double: 0.0012

Most types include methods with convenient aliases for the to methods.

valkw:Double= load toKilowatts // Double: 1200.0valmw:Double= load toMegawatts // Double: 1.20valgw:Double= load toGigawatts // Double: 0.0012

NOTE - It is important to use the to method for extracting the numeric value, as this ensures you will be getting the numeric value for the desired unit. Quantity.value should not be accessed directly. To prevent improper usage, direct access to the Quantity.value field may be deprecated in a future version.

Creating strings formatted in the desired unit:

valkw:String= load toString Kilowatts// String: “1200.0 kW”valmw:String= load toString Megawatts// String: “1.2 MW”valgw:String= load toString Gigawatts// String: “0.0012 GW”

Creating Tuple2(Double, String) that includes a numeric value and unit symbol:

valload:Power=Kilowatts(1200)
valkw:Tuple2= load toTuple // Tuple2: (1200, "kW")valmw:Tuple2= load toTuple Megawatts// Tuple2: (1.2, "MW)valgw:Tuple2= load toTuple Gigawatts// Tuple2: (0.0012, "GW")

This can be useful for passing properly scaled quantities to other processes that do not use Squants, or require use of more basic types (Double, String)

Simple console based conversions (using DSL described below)

1.kilograms to Pounds// Double: 2.2046226218487757 
kilogram / pound // Double: 2.20462262184877572.1.pounds to Kilograms// Double: 0.952543977 2.1.pounds / kilogram // Double: 0.952543977100.C to Fahrenheit// Double: 212.0

Mapping over Quantity values

Apply a Double => Double operation to the underlying value of a quantity, while preserving its type and unit.

valload=Kilowatts(2.0) // 2.0 kWvalnewLoad= load.map(v => v *2+10) // Power: 14.0 kW

The q.map(f) method effectively expands to q.unit(f(q.to(q.unit))

Approximations

Create an implicit Quantity value to be used as a tolerance in approximations. Then use the approx method (or =~, ~=, ≈ operators) like you would use the equals method (== operator).

implicitvaltolerance=Watts(.1) // implicit Power: 0.1 W valload=Kilowatts(2.0) // Power: 2.0 kWvalreading=Kilowatts(1.9999) // Power: 1.9999 kW// uses implicit tolerance
load =~ reading should be(true)
load ≈ reading should be(true)
load approx reading should be(true)

The =~ and ≈ are the preferred operators as they have the correct precedence for equality operations. The ~= is provided for those who wish to use a more natural looking approx operator using standard characters. However, because of its lower precedence, user code may require parenthesis around these comparisons.

Vectors

All Quantity types in Squants represent the scalar value of a quantity. That is, there is no direction information encoded in any of the Quantity types. This is true even for Quantities which are normally vector quantities (ie. Velocity, Acceleration, etc).

Vector quantities in Squants are implemented as case classes that takes a variable parameter list of like quantities representing a set of point coordinates in Cartesian space.
The SVector object is a factory for creating DoubleVectors and QuantityVectors. The dimensionality of the vector is determined by the number of arguments. Most basic vector operations are currently supported (addition, subtraction, scaling, cross and dot products)

valvector:QuantityVector[Length] =SVector(Kilometers(1.2), Kilometers(4.3), Kilometers(2.3))
valmagnitude:Length= vector.magnitude // returns the scalar value of the vectorvalnormalized= vector.normalize(Kilometers) // returns a corresponding vector scaled to 1 of the given unitvalvector2:QuantityVector[Length] =SVector(Kilometers(1.2), Kilometers(4.3), Kilometers(2.3))
valvectorSum= vector + vector2 // returns the sum of two vectorsvalvectorDiff= vector - vector2 // return the difference of two vectorsvalvectorScaled= vector *5// returns vector scaled 5 timesvalvectorReduced= vector /5// returns vector reduced 5 timevalvectorDouble= vector /5.meters // returns vector reduced and converted to DoubleVectorvaldotProduct= vector * vectorDouble // returns the Dot Product of vector and vectorDoublevalcrossProduct= vector crossProduct vectorDouble // currently only supported for 3-dimensional vectors

Simple non-quantity (Double based) vectors are also supported.

valvector:DoubleVector=SVector(1.2, 4.3, 2.3, 5.4) // a Four-dimensional vector

Dimensional conversions within Vector operations.

NOTE - This feature is currently under development and the final implementation being evaluated. The following type of operation is the goal.

valvectorLength=QuantityVector(Kilometers(1.2), Kilometers(4.3), Kilometers(2.3))
valvectorArea= vectorLength *Kilometers(2) // QuantityVector(2.4 km², 8.6 km², 4.6 km²)valvectorVelocity= vectorLength /Seconds(1) // QuantityVector(1200.0 m/s, 4300.0 m/s, 2300.0 m/s)valvectorDouble=DoubleVector(1.2, 4.3, 2.3)
valvectorLength= vectorDouble.to(Kilometers) // QuantityVector(1.2 km, 4.3 km, 2.3 km)

Currently dimensional conversions are supported by using the slightly verbose, but flexible map method.

valvectorLength=QuantityVector(Kilometers(1.2), Kilometers(4.3), Kilometers(2.3))
valvectorArea= vectorLength.map[Area](_ *Kilometers(2)) // QuantityVector(2.4 km², 8.6 km², 4.6 km²)valvectorVelocity= vectorLength.map[Velocity](_ /Seconds(1)) // QuantityVector(1200.0 m/s, 4300.0 m/s, 2300.0 m/s)valvectorDouble=DoubleVector(1.2, 4.3, 2.3)
valvectorLength= vectorDouble.map[Length](Kilometers(_)) // QuantityVector(1.2 km, 4.3 km, 2.3 km)

Convert QuantityVectors to specific units using the to or in method - much like Quantities.

valvectorLength=QuantityVector(Kilometers(1.2), Kilometers(4.3), Kilometers(2.3))
valvectorMetersNum= vectorLength.to(Meters) // DoubleVector(1200.0, 4300.0, 2300.0)valvectorMeters= vectorLength.in(Meters) // QuantityVector(1200.0 m, 4300.0 m, 2300.0 m)

Market Package

Market Types are similar but not quite the same as other quantities in the library. The primary type, Money, is a Dimensional Quantity, and its Units of Measure are Currencies. However, because the conversion multipliers between currency units can not be predefined, many of the behaviors have been overridden and augmented to realize correct behavior.

Money

A Quantity of purchasing power measured in Currency units. Like other quantities, the Unit of Measures are used to create Money values.

valtenBucks=USD(10) // Money: 10 USDvalsomeYen=JPY(1200) // Money: 1200 JPYvalgoldStash=XAU(50) // Money: 50 XAUvaldigitalCache=BTC(50) // Money: 50 BTC

Price

A Ratio between Money and another Quantity. A Price value is typed on a Quantity and can be denominated in any defined Currency.

Price = Money / Quantity

valthreeForADollar=USD(1) /Each(3) // Price[Dimensionless]: 1 USD / 3 eavalenergyPrice=USD(102.20) /MegawattHours(1) // Price[Energy]: 102.20 USD / megawattHourvalmilkPrice=USD(4) /UsGallons(1) // Price[Volume]: 4 USD / gallonvalcostForABunch= threeForADollar *Dozen(10) // Money: 40 USDvalenergyCost= energyPrice *MegawattHours(4) // Money: 408.80 USDvalmilkQuota= milkPrice *USD(20) // Volume: 5 gal

FX Support

Currency Exchange Rates are used to define the conversion factors between currencies

// create an exchange ratevalrate=CurrencyExchangeRate(USD(1), JPY(100))
// ORvalrate=USD/JPY(100)
// ORvalrate=JPY(100) ->USD(1)
// ORvalrate=JPY(100) toThe USD(1)
valsomeYen:Money=JPY(350)
valsomeBucks:Money=USD(23.50)
// Use the convert method which automatically converts the money to the 'other' currencyvaldollarAmount:Money= rate.convert(someYen) // Money: 3.5 USDvalyenAmount:Money= rate.convert(someBucks) // Money: 2360 JPY// or just use the * operator in either direction (money * rate, or rate * money)valdollarAmount2:Money= rate * someYen // Money: 3.5 USDvalyenAmount2:Money= someBucks * rate // Money: 2360 JPY

Money Context

A MoneyContext can be implicitly declared to define default settings and applicable exchange rates within its scope. This allows your application to work with a default currency based on an application configuration or other dynamic source. It also provides support for updating exchange rates and using those rates for automatic conversions between currencies. The technique and frequency chosen for exchange rate updates is completely in control of the application.

valexchangeRates=List(USD/CAD(1.05), USD/MXN(12.50), USD/JPY(100))
implicitvalmoneyContext= defaultMoneyContext withExchangeRates exchangeRates
valsomeMoney=Money(350) // 350 in the default CurvalusdMoney:Money= someMoney in USDvalusdBigDecimal:BigDecimal= someMoney to USDvalyenCost:Money= (energyPrice *MegawattHours(5)) in JPYvalnorthAmericanSales:Money= (CAD(275) +USD(350) +MXN(290)) in USD

Quantity Ranges

Used to represent a range of Quantity values between an upper and lower bound

valload1:Power=Kilowatts(1000)
valload2:Power=Kilowatts(5000)
valrange:QuantityRange[Power] =QuantityRange(load1, load2)

Use multiplication and division to create a Seq of ranges from the original

// Create a Seq of 10 sequential ranges starting with the original and each the same size as the originalvalrs1= range *10// Create a Seq of 10 sequential ranges each 1/10th of the original sizevalrs2= range /10// Create a Seq of 10 sequential ranges each with a size of 400 kilowattsvalrs3= range /Kilowatts(400)

Apply foreach, map and foldLeft/foldRight directly to QuantityRanges with a divisor

// foreach over each of the 400 kilometer ranges within the range
range.foreach(Kilometers(400)) {r =>???}
// map over each of 10 even parts of the range
range.map(10) {r =>???}
// fold over each 10 even parts of the range
range.foldLeft(10)(0) {(z, r) =>???}

NOTE - Because these implementations of foreach, map and fold* take a parameter (the divisor), these methods are not directly compatible with Scala's for comprehensions. To use in a for comprehension, apply the * or / operators as described above to create a Seq from the Range.

for {
interval <- (0.seconds to 1.seconds) *60// 60 time ranges, 0s to 1s, 1s to 2s, ...., 59s to 60s
...
} yield ...

Natural Language DSL

Implicit conversions give the DSL some features that allows user code to express quantities in a more naturally expressive and readable way.

Create Quantities using Unit Of Measure Factory objects (no implicits required)

valload=Kilowatts(100)
valtime=Hours(3.75)
valmoney=USD(112.50)
valprice=Price(money, MegawattHours(1))

Create Quantities using Unit of Measure names and/or symbols (uses implicits)

valload1=100 kW // Simple expressions don’t need dotsvalload2=100 megaWatts
valtime=3.hours +45.minutes // Compound expressions may need dots

Create Quantities using operations between other Quantities

valenergyUsed=100.kilowatts * (3.hours +45.minutes)
valprice=112.50.USD/1.megawattHours
valspeed=55.miles /1.hours

Create Quantities using formatted Strings

valload=Power("40 MW") // 40 MW

Create Quantities using Tuples

valload=Power((40, "MW")) // 40 MW

Use single unit values to simplify expressions

// Hours(1) == 1.hours == hourvalramp=100.kilowatts / hour
valspeed=100.kilometers / hour
// MegawattHours(1) == 1.megawattHours == megawattHour == MWhvalhi=100.dollars /MWhvallow=40.dollars / megawattHour

Implicit conversion support for using Double on the left side of operations

valprice=10/ dollar // 1 USD / 10 eavalfreq=60/ second // 60 Hzvalload=10*4.MW// 40 MW

Create Quantity Ranges using to or plusOrMinus (+-) operators

valrange1=1000.kW to 5000.kW // 1000.kW to 5000.kWvalrange2=5000.kW plusOrMinus 1000.kW // 4000.kW to 6000.kWvalrange2=5000.kW +-1000.kW // 4000.kW to 6000.kW

Numeric Support

Most Quantities that support implicit conversions also include an implicit Numeric object that can be imported to your code where Numeric support is required. These follow the following pattern:

importsquants.mass.MassConversions.MassNumericvalsum=List(Kilograms(100), Grams(34510)).sum

NOTE - Because a quantity can not be multiplied by a like quantity and return a like quantity, the Numeric.times operation of numeric is implemented to throw an UnsupportedOperationException for all types except Dimensionless.

The MoneyNumeric implementation is a bit different than the implementations for other quantity types in a few important ways.

1. MoneyNumeric is a class, not an object like the others.
2. To create a MoneyNumeric value there must be an implicit MoneyContext in scope.
3. The MoneyContext must contain applicable exchange rates if you will be applying cross-currency Numeric ops.

The following code provides a basic example for creating a MoneyNumeric:

importMoneyConversions._implicitvalmoneyContext= defaultMoneyContext
implicitvalmoneyNum=newMoneyNumeric()
valsum=List(USD(100), USD(10)).sum

Type Hierarchy

The type hierarchy includes the following core types: Quantity, Dimension, and UnitOfMeasure

Quantity and Dimension

A Dimension represents a type of Quantity. For example: Mass, Length, Time, etc.

A Quantity represents a dimensional value or measurement. A Quantity is a combination of a numeric value and a unit. For example: 2 lb, 10 km, 3.4 hr.

Squants has built in support for 54 quantity dimensions.

Unit of Measure

UnitOfMeasure is the scale or multiplier in which the Quantity is being measured. Squants has built in support for over 257 units of measure

For each Dimension a set of UOM objects implement a primary UOM trait typed to that Quantity. The UOM objects define the unit symbols, conversion factors, and factory methods for creating Quantities in that unit.

Quantity Implementations

The code for specific implementations include

• A class representing the Quantity including cross-dimensional operations
• A companion object representing the Dimension and set of available units
• A base trait for its Units
• A set of objects defining specific units, their symbols and conversion factors

This is an abbreviated example of how a Quantity type is constructed:

classLength(valvalue:Double, valunit:LengthUnit) extendsQuantity[Length] { ... }
objectLengthextendsDimension[Length] { ... }
traitLengthUnitextendsUnitOfMeasure[Length] { ... }
objectMetersextendsLengthUnit { ... }
objectYardsextendsLengthUnit { ... }

The apply method of the UOM objects are implemented as factories for creating Quantity values.

vallen1:Length=Meters(4.3)
vallen2:Length=Yards(5)

Squants currently supports 257 units of measure

Time Derivatives

Special traits are used to establish a time derivative relationship between quantities.

For example Velocity is the 1st Time Derivative of Length (Distance), Acceleration is the 2nd Time Derivative.

classLength( ... ) extendsQuantity[Length] withTimeIntegral[Velocity]
...
classVelocity( ... ) extendsQuantity[Velocity] withTimeDerivative[Length] withTimeIntegral[Acceleration]
...
classAcceleration( ... ) extendsQuantity[Acceleration] withTimeDerivative[Velocity]

These traits provide operations with time operands which result in correct dimensional transformations.

valdistance:Length=Kilometers(100)
valtime:Time=Hours(2)
valvelocity:Velocity= distance / time
valacc:Acceleration= velocity /Seconds(1)
valgravity=32.feet / second.squared

// Power is the 1st Time Derivative of Energy, PowerRamp is the 2ndvalpower=Kilowatts(100)
valtime:Time=Hours(2)
valenergy= power * time
valramp=Kilowatt(50) /Hours(1)

Use Cases

Dimensional Analysis

The primary use case for Squants, as described above, is to produce code that is typesafe within domains that perform dimensional analysis.

valenergyPrice:Price[Energy] =45.25.money / megawattHour
valenergyUsage:Energy=345.kilowatts *5.4.hours
valenergyCost:Money= energyPrice * energyUsage
valdodgeViper:Acceleration=60.miles / hour /3.9.seconds
valspeedAfter5Seconds:Velocity= dodgeViper *5.seconds
valtimeTo100MPH:Time=100.miles / hour / dodgeViper
valdensity:Density=1200.kilograms / cubicMeter
valvolFlowRate:VolumeFlowRate=10.gallons / minute
valflowTime:Time=30.minutes
valtotalMassFlow:Mass= volFlowRate * flowTime * density

Domain Modeling

Another excellent use case for Squants is stronger typing for fields in your domain model. This is OK ...

caseclassGenerator(
id: String,
maxLoadKW: Double,
rampRateKWph: Double,
operatingCostPerMWh: Double,
currency: String,
maintenanceTimeHours: Double)
...
valgen1=Generator("Gen1", 5000, 7500, 75.4, "USD", 1.5)
valgen2=Generator("Gen2", 100, 250, 2944.5, "JPY", 0.5)

... but this is much better

caseclassGenerator(
id: String,
maxLoad: Power,
rampRate: PowerRamp,
operatingCost: Price[Energy],
maintenanceTime: Time)
...
valgen1=Generator("Gen1", 5MW, 7.5.MW/hour, 75.4.USD/MWh, 1.5 hours)
valgen2=Generator("Gen2", 100 kW, 250 kWph, 2944.5.JPY/MWh, 30 minutes)

Anticorruption Layers

Create wrappers around external services that use basic types to represent quantities. Your application code then uses the ACL to communicate with that system thus eliminating the need to deal with type and scale conversions in multiple places throughout your application logic.

classScadaServiceAnticorruption(valservice:ScadaService) {
// ScadaService returns meter load as Double representing MegawattsdefgetLoad:Power=Megawatts(service.getLoad(meterId))
}
// ScadaService.sendTempBias requires a Double representing FahrenheitdefsendTempBias(temp: Temperature) =
service.sendTempBias(temp.to(Fahrenheit))
}

Implement the ACL as a trait and mix in to the application's services where needed.

traitWeatherServiceAntiCorruption {
valservice:WeatherServicedefgetTemperature:Temperature=Celsius(service.getTemperature)
defgetIrradiance:Irradiance=WattsPerSquareMeter(service.getIrradiance)
}

Extend the pattern to provide multi-currency support

classMarketServiceAnticorruption(valservice:MarketService)
(implicitvalmoneyContext:=MoneyContext) {
// MarketService.getPrice returns a Double representing $/MegawattHourdefgetPrice:Price[Energy] =
(USD(service.getPrice) in moneyContext.defaultCurrency) / megawattHour
// MarketService.sendBid requires a Double representing $/MegawattHour// and another Double representing the max amount of energy in MegawattHoursdefsendBid(bid: Price[Energy], limit: Energy) =
service.sendBid((bid * megawattHour) to USD, limit to MegawattHours)
}

Build Anticorruption into Akka routers

// LoadReading message used within a Squants enabled application contextcaseclassLoadReading(meterId: String, time: Long, load: Power)
classScadaLoadListener(router: Router) extendsActor {
defreceive= {
// ScadaLoadReading - from an external service - sends load as a string// eg, “10.3 MW”, “345 kW”case msg @ScadaLoadReading(meterId, time, loadString) ⇒// Parse the string and on success emit the Squants enabled event to routeesPower(loadString) match {
caseSuccess(p) => router.route(LoadReading(meterId, time, p), sender())
caseFailure(e) =>// react to QuantityStringParseException
}
}
}

... and REST API's with contracts that require basic types

traitLoadRouteextendsHttpService {
defrepo:LoadRepositoryvalloadRoute= {
path("meter-reading") {
// REST API contract requires load value and units in different fields// Units are string values that may be 'kW' or 'MW'
post {
parameters(meterId, time, loadDouble, unit) { (meterId, time, loadDouble, unit) =>
complete {
valload= unit match {
case"kW"=>Kilowatts(loadDouble)
case"MW"=>Megawatts(loadDouble)
}
repo.saveLoad(meterId, time, load)
}
}
} ~// REST API contract requires load returned as a number representing megawatts
get {
parameters(meterId, time) { (meterId, time) =>
complete {
repo.getLoad(meterId, time) to Megawatts
}
}
}
}
}
}

Contributors

• Gary Keorkunian (garyKeorkunian)
• Jeremy Apthorp (nornagon)
• Steve Barham (stevebarham)
• Derek Morr (derekmorr)
• rmihael (rmihael)
• Florian Nussberger (fnussber)

Caveats

Code is offered as-is, with no implied warranty of any kind. Comments, criticisms, and/or praise are welcome, especially from scientists, engineers and the like.