Workaround for loading old .jld2 files

[ArneSpang]

If you are loading an old .jld2 file that contains a GeoUnits object, you will encounter this warning

┌ Warning: saved type GeoUnits{GEO} is missing field chemicaldiffusion in workspace type; reconstructing
└ @ JLD2 ~/.julia/packages/JLD2/nPYlZ/src/data/reconstructing_datatypes.jl:193

If you then want to use dimensionalize with this GeoUnits object, you will get an error message because JLD2 was not able to properly load it. I discussed this with @albert-de-montserrat and we did not find a way to fix this, so I am showing a workaround for people that run into the same problem. This assumes that the GeoUnits object in your old file is called CD

julia> using GeoParams, JLD2

julia> d = load("oldFile.jld2");
┌ Warning: saved type GeoUnits{GEO} is missing field chemicaldiffusion in workspace type; reconstructing
└ @ JLD2 ~/.julia/packages/JLD2/nPYlZ/src/data/reconstructing_datatypes.jl:193

julia> CD = d["CD"];

julia> CD2 = GEO_units(length=CD.length, temperature=CD.temperature, stress=CD.stress, viscosity=CD.viscosity);

You can now use CD2 to inside dimensionalize and nondimensionalize again

[boriskaus]

thanks for reporting. Perhaps its worthwhile to add an upgrade_GeoUnits function to GeoParams that does this?

[albert-de-montserrat]

Note that this happens only if one tries to open a JLD2 file saved on GeoParams <= 0.6.8 using GeoParams >=0.7.0. The reasons is that chemical diffusion was added to GeoUnits in the latest GP versions so the old JLD2 file does not have it.

[boriskaus]

I see that; yet it cannot be excluded that we have further additions in the future, which would be handled in that case by upgrading the function

[ArneSpang]

function upgrade_GeoUnits(a) 
    return GEO_units(length=a.length, temperature=a.temperature, stress=a.stress, viscosity=a.viscosity) 
end

This would do the trick currently

[boriskaus]

I would slightly modify it:

function upgrade_GeoUnits(a::GEO_units) 
    return GEO_units(length=a.length, temperature=a.temperature, stress=a.stress, viscosity=a.viscosity) 
end

can you make a PR?

[ArneSpang]

I would slightly modify it:

function upgrade_GeoUnits(a::GEO_units)
return GEO_units(length=a.length, temperature=a.temperature, stress=a.stress, viscosity=a.viscosity)
end

can you make a PR?

I don't think this one works because a will be some weird type

julia> CD = d["CD"]
Reconstruct@GeoUnits{GEO}(Any[600 °C, 10 km, 100 MPa, 0.03168808781402895 ❓, 1.0e20 Pa s, 17463//20 K, 1.0e12 s, 10000 m, 100000000 Pa, 1.0e36 kg, 10000 m, 1.0e36 kg, 1.0e12 s, 17463//20 K, 1 mol, 1.0e12 s, 1.0e16 kg m s^-2.0, 1.0e20 kg m^2.0 s^-2.0, 1.0e8 kg m^2.0 s^-3.0, 100000000 m^2.0, 1000000000000 m^3.0, 1.0e-8 m s^-1.0, 1.0e24 kg m^-3.0, 1.0e-20 m s^-2.0, 1.0e16 kg m s^-2.0, 1.0e-12 s^-1.0, 1.1452785890167782e-19 m^2.0 K^-1.0 s^-2.0, 11.452785890167783 kg m K^-1.0 s^-3.0, 3.15576e7, 1.0e6, 3.15576e9])

[ArneSpang]

Would have to be this:

function upgrade_GeoUnits(a::JLD2.ReconstructedMutable)
    return GEO_units(length=a.length, temperature=a.temperature, stress=a.stress, viscosity=a.viscosity) 
end

for a PR, where would I put it?

[albert-de-montserrat]

I guess it should go into Units.jl

[albert-de-montserrat]

Would have to be this:

function upgrade_GeoUnits(a::JLD2.ReconstructedMutable)
return GEO_units(length=a.length, temperature=a.temperature, stress=a.stress, viscosity=a.viscosity)
end

for a PR, where would I put it?

This will fail as JLD2 is not in the Project.toml of GeoParams. I would leave it fully generic without type signature. It will crash anyway if a is of the wrong type