Closed GoogleCodeExporter closed 9 years ago
PS: the exact version is cantera-2.0.0, and the third statement actually works
(i.e. print gas.atomicWeights( gas.elementNames() ) )
Original comment by ischo...@gmail.com
on 9 Mar 2013 at 7:33
Everything is working here as expected.
- For the first two examples, the documentation for the atomicWeights method
specifies that it takes a *sequence* of elements. The string 'Ar' is a sequence
of two characters, neither of which are elements in the gas, so you get an
exception. If you call "gas.atomicWeights(['Ar'])" it will work fine.
- There is no required correspondence between the species names and the element
names. Cantera defines all the element names to have only the first letter
capitalized. The species names in this case are defined by the GRI 3.0
mechanism, which uses all-caps species identifiers.
- The fourth statement fails because you're asking for the *molecular weights*
of the pure elements, which aren't necessarily in the list of species by the
same name (or at all).
Original comment by yarmond
on 12 Mar 2013 at 11:15
Thanks, yarmond ...
Your points are technically correct, but I'd dispute that this renders my
report 'invalid':
- "gas.molecularWeights('H2')" works, and gas.molecularWeights('AR') works, so
it's not a stretch to expect "gas.atomicWeights('Ar')" to exhibit similar
behavior.
- while there are no required correspondences between species names and element
names, it would make sense to make them correspond: if it walks like a duck and
quacks like a duck it is probably a duck ... btw, the pure element 'Ar' is
indeed the same as the species 'AR' (I'd agree with your point of elements and
species being independent if the element names were hard-coded in cantera, but
the call "gas.elementNames()" indicates that the element information is pulled
from the mechanism.)
Just my 2 cents. I admit that both fixes are more like 'papercuts', rather than
major issues ...
Original comment by ischo...@gmail.com
on 13 Mar 2013 at 1:34
Don't read too much into the status "invalid". There are only a few statuses
that indicate an issue is closed with no corresponding change.
The element names are actually essentially hardcoded. Every Cantera input file
uses the elements as defined in the file "elements.xml", which uses the mixed
case convention for the element names.
Species and elements are distinct entities as far as Cantera is concerned. The
molecularWeights method expects a list of species names. Just because there is
a species whose chemical formula is 'Ar' does not mean that there is a species
by that name.
Original comment by yarmond
on 13 Mar 2013 at 3:05
Original issue reported on code.google.com by
ischo...@gmail.com
on 9 Mar 2013 at 7:26