dict problem

[Alistair King]

Hi,

ive been trying to update a dictionary containing a molecular formula, but seem to be getting this error:


Traceback (most recent call last):
  File "DS1excessH2O.py", line 242, in ?
    updateDS1v(FCas, C, XDS)
NameError: name 'C' is not defined

dictionary is: 

DS1v = {'C': 6, 'H': 10, 'O': 5}



#'Fxas' in each case will be integers but 'atoms' should be a float

def updateDS1v(Fxas, x, XDS):
    while Fxas != 0:
        atoms = DS1v.get('x') + Fxas*XDS
        DS1v[x] = atoms

updateDS1v(FCas, C, XDS)
updateDS1v(FHas, H, XDS)
updateDS1v(FOas, O, XDS)
updateDS1v(FNas, N, XDS)
updateDS1v(FSas, S, XDS)
updateDS1v(FClas, Cl, XDS)
updateDS1v(FBras, Br, XDS)
updateDS1v(FZnas, Zn, XDS)
print DS1v

I know there is probably a simple solution but im quite new to python and am lost?


Ali


-- 
Dr. Alistair King
Research Chemist,
Laboratory of Organic Chemistry,
Department of Chemistry,
Faculty of Science
P.O. Box 55 (A.I. Virtasen aukio 1)
FIN-00014 University of Helsinki
Tel. +358 9 191 50392, Mobile +358 (0)50 5279446
Fax +358 9 191 50366