Expression contains an invalid NaN constant. This could be produced by `Inf - Inf`.

[kdheepak]

If this is a question, something isn't working or an idea please start a Q&A discussion in the Discussion tab Open a bug report only if you can provide the details below

Describe the bug

If I rl = get_ramp_limits(g) and set them back using set_ramp_limits!(g, rl), the build in PowerSimulations seems to fail.

That is, if I have the following code:

    sys = create_sys()
    for g in get_components(ThermalStandard, sys)
        rl = get_ramp_limits(g)
        set_ramp_limits!(g, rl)
    end
    op_problem = ...
    build!(op_problem)

I end up with the following error when adding the linear ramp constraints

┌ Error: DecisionModel Build Failed
│   exception =
│    Expression contains an invalid NaN constant. This could be produced by `Inf - Inf`.
│    Stacktrace:
│      [1] error(s::String)
│        @ Base ./error.jl:35
│      [2] _assert_isfinite(a::AffExpr)
│        @ JuMP ~/.julia/packages/JuMP/0STkJ/src/aff_expr.jl:554
│      [3] MathOptInterface.ScalarAffineFunction(a::AffExpr)
│        @ JuMP ~/.julia/packages/JuMP/0STkJ/src/aff_expr.jl:587
│      [4] moi_function
│        @ ~/.julia/packages/JuMP/0STkJ/src/aff_expr.jl:630 [inlined]
│      [5] moi_function
│        @ ~/.julia/packages/JuMP/0STkJ/src/constraints.jl:483 [inlined]
│      [6] add_constraint(model::Model, con::ScalarConstraint{AffExpr, MathOptInterface.LessThan{Float64}}, name::String)
│        @ JuMP ~/.julia/packages/JuMP/0STkJ/src/constraints.jl:624
│      [7] add_linear_ramp_constraints!(container::PowerSimulations.OptimizationContainer, T::Type{RampConstraint}, U::Type{ActivePowerVariable}, devices::InfrastructureSystems.FlattenIteratorWrapper{ThermalStandard}, model::DeviceModel{ThermalStandard, ThermalStandardDispatch}, X::Type{CopperPlatePowerModel})
│        @ PowerSimulations ~/gitrepos/PowerSimulations.jl/src/devices_models/devices/common/rateofchange_constraints.jl:94
...

To Reproduce

Here's the code I'm using to reproduce this issue:

using PowerSystems
const PSY = PowerSystems
using PowerSimulations
const PSI = PowerSimulations
using InfrastructureSystems

using Dates
using DataFrames
using TimeSeries

using Xpress
using JuMP
using CSV
using DelimitedFiles

function create_rts_gmlc_system(
    repo;
    time_series_resolution = Dates.Hour(1),
    try_deserialize = true,
    kwargs...,
)
    rts_data = joinpath(repo, "RTS_Data")
    src_data = joinpath(rts_data, "SourceData")
    siip_data = joinpath(rts_data, "FormattedData", "SIIP")
    data = PowerSystemTableData(
        src_data,
        100.0,
        joinpath(siip_data, "user_descriptors.yaml"),
        generator_mapping_file = joinpath(siip_data, "generator_mapping.yaml"),
        timeseries_metadata_file = joinpath(siip_data, "timeseries_pointers.json"),
    )
    sys = System(data; time_series_resolution = time_series_resolution, kwargs...)
    set_units_base_system!(sys, "system_base")
    return sys
end

function main()

    repo = expanduser("~/gitrepos/RTS-GMLC")
    sys = create_rts_gmlc_system(repo)

    ### ADD THESE LINES
    for g in get_components(ThermalStandard, sys)
        rl = get_ramp_limits(g)
        set_ramp_limits!(g, rl)
    end
    ### ADD THESE LINES

    horizon = 24;
    interval = Dates.Hour(24);
    transform_single_time_series!(sys, horizon, interval)

    template_uc = ProblemTemplate()

    set_device_model!(template_uc, ThermalStandard, ThermalStandardDispatch)

    solver = optimizer_with_attributes(Xpress.Optimizer, "MIPRELSTOP" => 0.0001, "OUTPUTLOG" => 1)
    op_problem = DecisionModel(
        template_uc,
        sys,
        horizon = 2,
        optimizer = solver,
        initial_time = Dates.DateTime("2020-01-01T00:00:00"),   # "2020-07-30T00:00:00"
    )

    build!(op_problem, output_dir = mktempdir())

    psi_container = PSI.get_optimization_container(op_problem)
    open("test.txt","w") do f
        print(f,psi_container.JuMPmodel)
    end
    op_problem
end

main()

Expected behavior

No error should occur when a get and set is used with the exact same data.

cc @Nongchao

[jd-lara]

I don't think that is guaranteed in PowerSystems that this will return the same thing

   for g in get_components(ThermalStandard, sys)
        rl = get_ramp_limits(g)
        set_ramp_limits!(g, rl)
    end

depends on the unit settings.

But we should definitely catch the Infs before the build

[jd-lara]

Issue is stale and hasn't been repeated.