def test_bind(self):
""" """
ethanol = formula.Formula('C2H5OH')
aceticacid = formula.Formula('CH3COOH')
diethylester = ethanol.bind(aceticacid)
assert diethylester.formula == 'C4H8O2'
def test_add(self):
""" """
aceticacid = formula.Formula('CH3COOH')
acetate = aceticacid - formula.Formula('H', charge = 1)
assert acetate.charge == -1
acetate += formula.Formula('H', charge = 1)
assert abs(acetate.mass - aceticacid.mass) < 0.0000001
def test_bind_split(self):
""" """
ethanol = formula.Formula('C2H5OH')
aceticacid = formula.Formula('CH3COOH')
diethylester = ethanol.bind(aceticacid)
ethanol2, aceticacid2 = diethylester.split(ethanol)
assert ethanol.formula == ethanol2.formula
assert aceticacid.formula == aceticacid2.formula
def mz_lowest_error_from_name(
self,
measured_mz,
adduct,
name=None,
**kwargs,
):
"""
Regarding a measured m/z and an assumed adduct type and name
returns the m/z of the record with matching name and lowest error.
"""
exmasses = self.masses_from_name(name=name, **kwargs)
if exmasses is not None:
adduct_method = (settings.get('ex2ad_all')[adduct])
addmasses = np.array([
getattr(formula.Formula(exmass), adduct_method)()
for exmass in exmasses
])
ppms = np.array(
[common.ppm(addmass, measured_mz) for addmass in addmasses])
return addmasses[np.argmin(np.abs(ppms))]
def process_line(l):
"""
Parameters
----------
l :
Returns
-------
"""
l = l.split('\t')
mass = (formula.Formula(l[1]).mass
if l[1] else float(l[0]) if l[0] else None)
self.constraints[l[2]] = (
tuple(
fragment.FragConstraint(
hg=constr.split(',')[0],
sub=(tuple(constr.split(',')[1:]) if ',' in constr else
()),
sph=constr.split('|')[1] if '|' in constr else None,
# no way at the moment to define chain
# type in file but later can be added easily
chaintype=None)
for constr in l[4].strip().split(';')) if l[4].strip() else
(
# an empty constraint to make sure anything matches
fragment.FragConstraint(), ))
return [mass, l[2], l[3], np.nan, np.nan, np.nan, get_charge(l[3])]
def __iter__(self, cores_only = False):
for i in range(len(self.cores)):
self.update_core(i)
for c in self.chlens:
self.c = c
for u in self.unsats:
self.u = u
if not self.c_u_diff(self.c, self.u):
continue
# implicit hydrogens
h = c * 2 + 2 - self.valence - 2 * u
p = self.get_prefix()
new_counts = self.counts.copy()
new_counts['C'] += c
new_counts['H'] += h
new_attrs = copy.deepcopy(self.attrs)
# `attrs` might contain methods which are called
# with the present instance passed and their returned
# value will be the attribute value of the
# iteration products
for k, v in iteritems(new_attrs.__dict__):
if hasattr(v, '__call__'):
setattr(new_attrs, k, v(self))
if self.chain_type and self.chain_attr and c > 0:
new_attrs.chain = self.get_chain()
new = self + formula.Formula(**new_counts)
new.attrs = new_attrs
new.c = c
new.u = u
new.get_prefix = lambda: p
new.variable_aliphatic_chain = (
self.variable_aliphatic_chain
)
new.name = self.getname(self)
# new.attrs.chain = self.get_chain()
yield new
if cores_only:
break
if cores_only:
break
def get_substituent(sub):
"""Creates a `Formula` object if the substituent is not
already an instance of `Formula` or `Substituent`.
Parameters
----------
sub :
Returns
-------
"""
return (
formula.Formula(sub)
if hasattr(sub, 'lower') or type(sub) is float
else formula.Formula(**sub)
if type(sub) is dict
else sub
)
def add_annotations(mol, record, exact_mass_formula_fallback=True):
"""
Parameters
----------
mol :
record :
exact_mass_formula_fallback :
(Default value = True)
Returns
-------
"""
mol.db_id = record[0]
mol.name = record[3]
if hasattr(mol, 'OBMol'):
mol.OBMol.SetTitle(record[2])
else:
mol.title = tuple(n.strip() for n in record[2:5] if n.strip())
mol.chebi = record[24] if len(record) > 24 else ''
mol.lipidmaps = record[25] if len(record) > 25 else ''
mol.hmdb = record[26] if len(record) > 26 else ''
mol.smiles = record[8]
mol.swl_exact_mass = float(record[14]) if record[14] else None
if not mol.swl_exact_mass and exact_mass_formula_fallback:
try:
# note: this is dangerous because the formula is sometimes
# dehydrogenated and charged state while exact mass
# should be uncharged with all hydrogenes
mol.swl_exact_mass = formula.Formula(record[11]).mass
except KeyError:
pass
mol.swl_formula = record[11]
mol.inchi = record[9]
mol.inchikey = record[10]
mol.level = record[1]
return mol
def mz_from_name(
self,
adduct,
name=None,
database_preference=None,
**kwargs,
):
exmass = self.mass_from_name(
name=name,
database_preference=database_preference,
**kwargs,
)
if exmass is not None:
adduct_method = (settings.get('ex2ad_all')[adduct])
return getattr(formula.Formula(exmass), adduct_method)()
def __iter__(self):
for rec in sdf.SdfReader.__iter__(self):
if ('EXACT_MASS' not in rec['annot']
or float(rec['annot']['EXACT_MASS']) == 0):
try:
exmass = formula.Formula(rec['annot']['FORMULA']).mass
except KeyError:
# if no exact mass it means
# this is a higher level category
continue
else:
exmass = float(rec['annot']['EXACT_MASS'])
names = [
rec['name'][nametype].strip()
for nametype in ('COMMON_NAME', 'SYSTEMATIC_NAME')
if nametype in rec['name']
]
if 'SYNONYMS' in rec['name']:
names.extend(n.strip()
for n in rec['name']['SYNONYMS'].split(';'))
names = [n.strip() for n in names if n.strip()]
hg, chainsum, chains = self.nameproc.process(names)
liprec = lipproc.LipidRecord(
lab=lipproc.LipidLabel(
db_id=rec['id'],
db='LipidMaps',
names=tuple(names),
formula=rec['annot']['FORMULA'],
),
hg=hg,
chainsum=chainsum,
chains=chains,
)
yield exmass, liprec
def test_calc_mass(self):
""" """
ethanol = formula.Formula('C2H5OH')
assert abs(ethanol.mass - 46.04186481376) < 0.0000001
# In[11]:
mass.expr('H + n')
# Hydrogensulphate ion:
# In[12]:
mass.expr('HSO4 + e')
# Additional attributes can be provided in keyword arguments to carry metadata.
# In[40]:
lactic_acid = formula.Formula('CH3CHOHCOOH', name='lactic acid')
lactic_acid.attrs.name
# A galactose:
# In[15]:
((2 * formula.Formula('C6H12O6')) - 'H2O').formula
# ## 2: Calculations with adducts
# In[4]:
from lipyd import mz
# This is an oleic acid. What is the mass of the [M-H]- adduct?