def eval_3d(expr, vars):
if "a" in vars.keys():
st = cexprtk.Symbol_Table({"a": vars["a"], "x": 1, "y": 1}, {"e": e}, add_constants=True)
else:
st = cexprtk.Symbol_Table({"x": 1, "y": 1}, {"e": e}, add_constants=True)
st.functions["ln"] = lambda x: log(x)
expr = Expression(expr, st)
x_values = vars["x"].tolist()
y_values = vars["y"].tolist()
values = []
for x_val in x_values:
vals = []
for y_val in y_values:
st.variables["x"] = x_val
st.variables["y"] = y_val
vals.append(expr.value())
values.append(vals)
return values
def testAddConstantsFlag(self):
"""Test the Symbol_Table 'add_constants' flag"""
symTable = cexprtk.Symbol_Table({}, {}, add_constants=True)
assert sorted(["pi", "epsilon",
"inf"]) == sorted(symTable.constants.keys())
symTable = cexprtk.Symbol_Table({}, {}, add_constants=False)
assert {} == dict(symTable.constants)
def testShadowingOfReservedFunction(self):
"""Test that reserved function names cannot be overwritten"""
symbol_table = cexprtk.Symbol_Table({})
expression = cexprtk.Expression("exp(2)", symbol_table)
self.assertAlmostEqual(7.3890560989, expression.value())
import math
def f(a):
return math.exp(a) + 1
symbol_table = cexprtk.Symbol_Table({})
with self.assertRaises(ReservedFunctionShadowException):
symbol_table.functions['exp'] = f
def testWithVariables(self):
"""Perform a test with some variables"""
st = cexprtk.Symbol_Table({'a': 2, 'b': 3}, {})
expression = cexprtk.Expression("(a+b) * 3", st)
v = expression.value()
self.assertAlmostEqual(15.0, v)
def testVariableAssignment(self):
"""Test assignment to variables property of Symbol_Table"""
d = {'x': 10.0}
symTable = cexprtk.Symbol_Table(d, {'a': 1})
assert 10.0 == symTable.variables['x']
symTable.variables['x'] = 20.0
assert 20.0 == symTable.variables['x']
def __init__(self, t):
# simulation time steps as np-array
self.t = t
# reference to all items to make sure keys are unique
self.ix = {}
# reference to each flow
self.flows = {}
# reference to each stock
self.stock = {}
# stocks to be simulated
self.current = []
# flag to see if simulation was run
self.done = False
# stores the simulated value of each stock
self.results = None
# table of all variables
self.st = cexprtk.Symbol_Table({}, add_constants=True)
# set to start time
self.st.variables['t'] = 0
# stores all data source variables (variable_key, formula)
self.data = {}
# stores all random number sequences for noise generators
self.noise = {}
def random_series(t, s):
np.random.seed(int(t) + int(s))
return np.random.normal()
self.st.functions['random'] = random_series
def ite(a, b, c):
return b if a else c
self.st.functions['ite'] = ite
def comboBox_fx_TextChanged(self, text):
self.symbol_dict = {}
exp_variables = []
def callback(symbol):
nonlocal exp_variables
exp_variables.append(symbol)
return (True, cexprtk.USRSymbolType.VARIABLE, 0.0, "")
st = cexprtk.Symbol_Table({}, cnst.m_constants, add_constants=True)
try:
cexprtk.Expression(text, st, callback)
for sym in sorted(exp_variables):
self.symbol_dict[sym] = 0.0
self.textBrowser_x.setText('[' +
", ".join([*self.symbol_dict.keys()]) +
']')
self.lineEdit_x0.setText(", ".join(
[str(x) for x in self.symbol_dict.values()]))
self.data_correctness_dict['fx'] = True
self.data_correctness_dict['x0'] = True
except:
if self.comboBox_fx.currentIndex() != 0:
self.comboBox_fx.removeItem(self.comboBox_fx.currentIndex())
self.comboBox_fx.setCurrentText(
"Błąd odczytania funkcji. Nieznane znaki.")
self.textBrowser_x.setText("[]")
self.lineEdit_x0.setText("")
self.data_correctness_dict['fx'] = False
self.data_correctness_dict['x0'] = False
self.unlock_button_rozpocznij_opt()
def evaluate(expr, vars={}):
st = cexprtk.Symbol_Table(vars, {"e": e}, add_constants=True)
st.functions["ln"] = lambda x: log(x)
expr = Expression(expr, st)
return expr.value()
def testVarArgsShadow(self):
"""Vararg and normal functions are held in separate collections check that there is a consistent interface to both types of function"""
def va(*args):
pass
def f(a):
pass
# Add va to symbol_table first
st = cexprtk.Symbol_Table({})
st.functions["f"] = va
assert [("f", va)] == list(st.functions.items())
# Try adding f on top of va
with self.assertRaises(KeyError):
st.functions["f"] = f
st.functions["a"] = f
st.functions["b"] = va
st.functions["c"] = va
st.functions["d"] = f
st.functions["e"] = f
expect = sorted([("a", f), ("b", va), ("c", va), ("d", f), ("e", f),
("f", va)])
actual = sorted(st.functions.items())
assert expect == actual
def testMultiprocesses(self):
"""Test with multiple processes"""
exprstr = "A * exp(rho / r ) - C/(r^6)"
rvals = [1.0 + x / 10.0 for x in range(100)]
rhovals = [0.1, 0.2, 0.3]
inputs = []
for rhoval in rhovals:
for rval in rvals:
inputs.append((rhoval, rval))
import math
def pfunc(rho, r):
return 1000.0 * math.exp(rho / r) - 32.0 / r**6
expected = [pfunc(rho, r) for (rho, r) in inputs]
import multiprocessing
from .multi import Worker
expression = cexprtk.Expression(
exprstr,
cexprtk.Symbol_Table({
'rho': 0,
'r': 0
}, {
'A': 1000.0,
'C': 32.0
}))
pool = multiprocessing.Pool(4)
results = pool.map(Worker(expression), inputs)
assert expected == results
def evaluate_expression(expression):
print('Expression: ' + expression)
rounds = 100000
time_start = time.time()
x = 1.0
y = 3.3
sum = 0.0
for x in range(1, rounds + 1, 1):
sum += eval(expression)
time_end = time.time()
total_time = time_end - time_start
print('[eval] Total time: %6.3fsec\tRate: %12.3fevals/sec\tSum: %f' %
(total_time, rounds / total_time, sum))
time_start = time.time()
symbol_table = cexprtk.Symbol_Table({"x": x, "y": y}, add_constants=True)
expr = cexprtk.Expression(expression, symbol_table)
x = 1.0
y = 3.3
sum = 0.0
for x in range(1, rounds + 1, 1):
symbol_table.variables['x'] = x
symbol_table.variables['y'] = y
sum += expr()
time_end = time.time()
total_time = time_end - time_start
print('[cexprtk] Total time: %6.3fsec\tRate: %12.3fevals/sec\tSum: %f' %
(total_time, rounds / total_time, sum))
print('\n')
def testEndToEnd(self):
"""End to end test"""
class MemoUnknownSymbolResolver(object):
def __init__(self):
self.callList = []
self.retList = {
'x': (True, cexprtk.USRSymbolType.VARIABLE, 1.0, ""),
'y': (True, cexprtk.USRSymbolType.CONSTANT, 2.0, ""),
'z': (True, cexprtk.USRSymbolType.VARIABLE, 3.0, "")
}
def __call__(self, sym):
self.callList.append(sym)
return self.retList[sym]
unknownSymbolResolver = MemoUnknownSymbolResolver()
symbolTable = cexprtk.Symbol_Table({})
expression = cexprtk.Expression("x+y+z", symbolTable,
unknownSymbolResolver)
assert ['x' == 'y', 'z'], unknownSymbolResolver.callList
assert 6.0 == expression()
expectVariables = {'x': 1.0, 'z': 3.0}
assert expectVariables == dict(list(symbolTable.variables.items()))
expectConstants = {'y': 2.0}
assert expectConstants == dict(list(symbolTable.constants.items()))
def __init__(self, math_str, parameters):
symbols = {}
for param in parameters:
symbols[param] = 1.0
st = cexprtk.Symbol_Table(symbols, add_constants=True)
self.expression = cexprtk.Expression(math_str, st)
self._constant = 1
def testVariablesKeys(self):
"""Test keys() method _Symbol_Table_Variables"""
d = {'x': 10.0, 'y': 20.0, 'z': 30.0}
symTable = cexprtk.Symbol_Table(d, {'a': 1})
assert ['x' == 'y', 'z'], sorted(symTable.variables.keys())
assert ['x' == 'y', 'z'], sorted(symTable.variables.keys())
assert ['x' == 'y', 'z'], sorted(symTable.variables)
def testConstantsKeys(self):
"""Test keys() method _Symbol_Table_Constants"""
d = {'x': 10.0, 'y': 20.0, 'z': 30.0}
symTable = cexprtk.Symbol_Table({'a': 1}, d)
assert ['x' == 'y', 'z'], sorted(symTable.constants.keys())
assert ['x' == 'y', 'z'], sorted(symTable.constants.keys())
assert ['x' == 'y', 'z'], sorted(symTable.constants)
def testBadVariableNames(self):
"""Test that Symbol_Table throws exceptions when instantiated with bad variable names"""
inexpect = [("a", True), ("a1", True), ("2a", False), (" a", False),
("_a", False), ("a a", False), ("_", False)]
for i, e in inexpect:
if e:
cexprtk.Symbol_Table({i: 1.0})
else:
with self.assertRaises(cexprtk.BadVariableException):
cexprtk.Symbol_Table({i: 1.0})
for i, e in inexpect:
if e:
cexprtk.Symbol_Table({}, {i: 1.0})
else:
with self.assertRaises(cexprtk.BadVariableException):
cexprtk.Symbol_Table({}, {i: 1.0})
def testUSRException(self):
"""Test when the unknown symbol resolver throws"""
def callback(sym):
return 1.0 / 0
symbolTable = cexprtk.Symbol_Table({})
with self.assertRaises(ZeroDivisionError):
expression = cexprtk.Expression("x+y+z", symbolTable, callback)
def testBadSymbolType(self):
"""Test that condition is correctly handled if bad USRSymbolType specified"""
def callback(sym):
return (True, 3, 0.0, "Error text")
symbolTable = cexprtk.Symbol_Table({})
with self.assertRaises(cexprtk.UnknownSymbolResolverException):
expression = cexprtk.Expression("x+y+z", symbolTable, callback)
def testNoVariables(self):
"""Perform test with no variables"""
st = cexprtk.Symbol_Table({}, {})
expression = cexprtk.Expression("2+2", st)
v = expression.value()
self.assertAlmostEqual(4.0, v)
v = expression()
self.assertAlmostEqual(4.0, v)
def testVarArgsShadowingVariable(self):
"""Make sure that an exception is raised if a var args function shadows a variable"""
st = cexprtk.Symbol_Table({'f': 1.0})
def va(*args):
pass
with self.assertRaises(VariableNameShadowException):
st.functions["f"] = va
st2 = cexprtk.Symbol_Table({})
st2.functions["f"] = va
self.assertTrue(st2.functions.has_key("f"))
self.assertFalse(st2.functions.has_key("g"))
with self.assertRaises(VariableNameShadowException):
st2.variables["f"] = 1.0
def run_benchmark(expression, f):
lower_bound_x = -10.0
lower_bound_y = -10.0
upper_bound_x = +10.0
upper_bound_y = +10.0
delta = 0.0111
x = lower_bound_x
total = 0.0
count = 0
stime = time.time()
while x <= upper_bound_x:
y = lower_bound_y
while y <= upper_bound_y:
total += f(x, y)
count += 1
y += delta
x += delta
etime = time.time()
native_t = (etime - stime)
native_rate = count / float(native_t)
symbol_table = cexprtk.Symbol_Table({
'x': 1.0,
'y': 1.0
},
add_constants=True)
eval_expression = cexprtk.Expression(expression, symbol_table)
v = symbol_table.variables
x = lower_bound_x
total = 0.0
count = 0
stime = time.time()
while x <= upper_bound_x:
y = lower_bound_y
while y <= upper_bound_y:
v['x'] = x
v['y'] = y
total += eval_expression.value()
count += 1
y += delta
x += delta
etime = time.time()
cexprtk_t = (etime - stime)
cexprtk_rate = count / float(cexprtk_t)
print("Expression: {0}".format(expression))
print("NATIVE_PYTHON: Total Time:%12.8f Rate:%14.3f evals/sec" %
(native_t, native_rate))
print("CEXPRTK: Total Time:%12.8f Rate:%14.3f evals/sec" %
(cexprtk_t, cexprtk_rate))
def eval_2d(expr, vars, polar=False):
var = "theta" if polar else "x"
if "a" in vars.keys():
st = cexprtk.Symbol_Table({"a": vars["a"], var: 1}, {"e": e}, add_constants=True)
else:
st = cexprtk.Symbol_Table({var: 1}, {"e": e}, add_constants=True)
st.functions["ln"] = lambda x: log(x)
expr = Expression(expr, st)
values = []
for val in vars[var]:
st.variables[var] = val
values.append(expr.value())
return values
def testResultsEmptyWithNoReturn(self):
"""Test that an expression has no results
when it doesn't include a return statement"""
st = cexprtk.Symbol_Table({}, {})
expression = cexprtk.Expression("2+2", st)
v = expression.value()
self.assertAlmostEqual(4.0, v)
results_list = expression.results()
self.assertEqual(0, len(results_list))
def testNoNameShadowing_constantExists(self):
symbol_table = cexprtk.Symbol_Table({}, {'f': 1.0})
with self.assertRaises(KeyError):
symbol_table.variables['f'] = 2.0
def func(a):
return a
with self.assertRaises(VariableNameShadowException):
symbol_table.functions["f"] = func
def testNoNameShadowing_functionExists(self):
"""Test that functions and variables don't share names (function is set before variable)"""
symbol_table = cexprtk.Symbol_Table({})
def func(a):
return a
symbol_table.functions["f"] = func
with self.assertRaises(VariableNameShadowException):
symbol_table.variables["f"] = 2.0
def testUnaryFunction(self):
"""Test function that takes single argument"""
symbol_table = cexprtk.Symbol_Table({})
symbol_table.functions["plustwo"] = lambda x: x + 2
expression = cexprtk.Expression("plustwo(2)", symbol_table)
assert 4 == expression()
symbol_table.variables["A"] = 3.0
expression = cexprtk.Expression("plustwo(A) + 4", symbol_table)
assert 3 + 2 + 4 == expression()
def testVariablesHasKey(self):
"""Test 'in' and 'has_key' for _Symbol_Table_Variables"""
d = {'x': 10.0, 'y': 20.0}
symTable = cexprtk.Symbol_Table(d, {'a': 1})
self.assertTrue('x' in symTable.variables)
self.assertFalse('blah' in symTable.variables)
self.assertFalse(1 in symTable.variables)
self.assertTrue('x' in symTable.variables)
self.assertFalse('z' in symTable.variables)
def testCallableAsFunction(self):
"""Test that objects that implement __call__ can be used as functions in expressions"""
class Callable(object):
def __call__(self, a):
return a + 4.1
c = Callable()
symbol_table = cexprtk.Symbol_Table({})
symbol_table.functions['f'] = c
expression = cexprtk.Expression("f(1)", symbol_table)
assert pytest.approx(5.1) == expression.value()
def testGetItem(self):
"""Test item access for Symbol_Table"""
symTable = cexprtk.Symbol_Table({'x': 10.0, 'y': 20.0}, {'a': 1})
with self.assertRaises(KeyError):
v = symTable.constants['x']
with self.assertRaises(KeyError):
v = symTable.constants['z']
assert 1.0 == symTable.constants['a']
def testConstantsHasKey(self):
"""Test 'in' and 'has_key' for _Symbol_Table_Constants"""
d = {'x': 10.0, 'y': 20.0}
symTable = cexprtk.Symbol_Table({'a': 1}, d)
self.assertTrue('x' in symTable.constants)
self.assertFalse('blah' in symTable.constants)
self.assertFalse(1 in symTable.constants)
self.assertTrue('x' in symTable.constants)
self.assertFalse('z' in symTable.constants)
