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customization - Extracting data from Data paclet



In the $UserBasePacletsDirectory there are lots of paclets that have only Data as an element. These are loaded via the DataPaclets` functionality using the standard form:


DataPaclets`ImportData[
pacletName<>"_"<>dataPart<>".wdx",
DataPaclets`GetDataPacletResource[pacletName<>"_"<>dataPart,
dataSubpart<>".wdx"]
]

E.g.:


DataPaclets`ImportData[
"ChemicalData_Index",

DataPaclets`GetDataPacletResource[
"ChemicalData_Index",
"Properties.wdx"
]
]

This only works though when the .wdx file has the standard "Expression" part, e.g.:


DataPaclets`ImportData[
"ChemicalData_Index",
DataPaclets`GetDataPacletResource[

"ChemicalData_Index",
"Index.wdx"
]
]

this fails.


On the other hand for these indices we can pull stuff like:


DataPaclets`ImportData[
"ChemicalData_Index",
DataPaclets`GetDataPacletResource[

"ChemicalData_Index",
"Index.wdx"
],
{"DataIndex", "Sources", "Data"}
]

Which will give us a long set of data specifying in what part we can find the actual data. For example we'll get something like "Part01" -> { ... } which seems to mean that the data for keys listed in that list can be found via:


DataPaclets`ImportData[
"ChemicalData_Part01",
DataPaclets`GetDataPacletResource[

"ChemicalData_Part01",
"Part01.wdx"
],
{"DataTable", "Index"} (* Note that now we find the DataTable element *)
]

The problem is that the return from this is just a long list of really large ints and I have no idea what they mean and how to convert them to proper data.


I want to make my own Data paclet, but unfortunately I need to know how to export my data to make it work.


Does anyone know how to convert this? I really have no idea what it's supposed to be as the numbers range from around 440k to roughly 6 mil




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