def expression_complexity(expr):
'''
Returns the complexity of the expression defined as the sum of the number
of leaves and nodes of the tree. TODO: better definition?
'''
if isinstance(expr, str):
expr = parse_to_sympy(expr)
if len(expr.args)==0:
return 1
else:
return 1+sum(map(expression_complexity, expr.args))
def replace_func(x, t, expr, temp_vars):
'''
TODO
'''
s_expr = parse_to_sympy(expr, local_dict=self.symbols)
for var in eqs.eq_names:
temp_vars_specific = dict([('_' + temp_var + '_' + var,
Symbol('_' + temp_var + '_' + var))
for temp_var in temp_vars])
self.symbols.update(temp_vars_specific)
temp_var_replacements = dict([(temp_var, temp_vars_specific['_' + temp_var + '_' + var])
for temp_var in temp_vars])
one_replacement = x.subs(SYMBOLS['x'], variables[var])
one_replacement = one_replacement.subs(temp_var_replacements)
s_expr = s_expr.subs(variables[var], one_replacement)
# replace time (important for time-dependent equations)
s_expr.subs(SYMBOLS['t'], t)
return s_expr
def __init__(self, description):
try:
parsed = DESCRIPTION.parseString(description, parseAll=True)
except ParseException as p_exc:
raise SyntaxError('Parsing failed: \n' + str(p_exc.line) + '\n' +
' '*(p_exc.column - 1) + '^\n' + str(p_exc))
self.statements = []
self.symbols = SYMBOLS.copy()
for element in parsed:
# Make sure to always re-use symbol objects for known symbols,
# otherwise the replacements go wrong
expression = parse_to_sympy(element.expression,
local_dict=self.symbols)
symbols = list(expression.atoms(Symbol))
self.symbols.update(dict([(symbol.name, symbol)
for symbol in symbols]))
if element.getName() == 'statement':
self.statements.append((element.identifier, expression))
elif element.getName() == 'output':
self.output = expression
else:
raise AssertionError('Unknown element name: %s' % element.getName())
def __init__(self, code, namespace=None, exhaustive=True, level=0):
super(Expression, self).__init__(code, namespace, exhaustive, level + 1)
self._sympy_expr = parse_to_sympy(self.code)
def translate_expression(self, expr):
expr = parse_to_sympy(expr)
return CCodePrinter().doprint(expr)