Docstring of methods

[lukmuk]

Hello Nicholas and other DTSA users,

is there a way to show the documentation string/help for methods in DTSA?
So far I cannot find a way to print it in DTSA's Jython console...

Example:

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m = material("SiO2")
help(m.addElementByStoiciometry()) # doesn't work
help(addElementByStoiciometry()) # doesn't work
help(addElementByStoiciometry) # doesn't work
dir(addElementByStoiciometry) # doesn't work also with dir
...


But I see that it expects two input args when trying to call the method:

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m.addElementByStoiciometry() # error: requires 2 input args


Currently I am looking at the Github source code to find the explanation: https://github.com/usnistgov/EPQ/blob/b9949d1e08ccea81907e0d7bd9d79fe7d1d4f365/src/gov/nist/microanalysis/EPQLibrary/Composition.java#L299
That works (e.g., here I see that it expects an element and a mole fraction as args), but is a bit more involved.

For "basic" functions that are not method of classes/objects, help works as expected, e.g.,

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help(windowTransmission)

Maybe I am overlooking something or is it a limitation of the Jython console?

Thanks for any help!

Kind regards,
lukmuk

[Nicholas Ritchie]

There is a little bit of a mismatch between Jython and Java.  As you note,

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> help(material)
material("TiO2",[density=4.27])
The function creates a Composition object by first checking the material database for a material with the specified name. If the material isn't in the database it will then attempt to parse the name as a chemical formula.  If both of these fail the method will return None.

works.   This is because I explicitly added help for functions implemented in Jython but Jython doesn't know how to look up the documentation for code developed in Java.  So,

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4> help(m.addElementByStoiciometry)
Java Method:
No arguments: addElementByStoiciometry()

is worse than non-helpful. It is incorrect.  As you note,

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m.addElementByStoiciometry(...) takes two arguments - an Element and an integer.  So

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4> m = material("SiO2")
5> m.addElementByStoiciometry(element("Fe"),1)
6> describe(m)
SiO2
Density 3 g/cm³
Element Z Mass Frac Norm Mass Atom Frac
Oxygen 8 0.140578 0.140578 0.333334
Silicon 14 0.123386 0.123386 0.166666
Iron 26 0.736036 0.736036 0.5
-- 21.989 1 1.0 1.0

You could also use

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epq.Element.Fe as an optimized version of

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element("Fe")

The best best is, as you discovered, to look up the source code for the EPQ library on Github. In this case,  https://github.com/usnistgov/EPQ/blob/master/src/gov/nist/microanalysis/EPQLibrary/Material.java

[lukmuk]

Hello Nicholas,

thanks for the quick reply and clarifications.
All makes sense now (Java and Python mixture) and using Github as documentation works well!

Kind regards,
lukmuk