def test_queue(self):
test_queue = Queue()
for i in range(0, 5):
test_queue.push(i)
counter = 0
while test_queue.is_empty() is not True:
self.assertTrue(test_queue.peek() == counter)
test_queue.pop()
counter += 1
self.assertTrue(test_queue.is_empty())
class Calculator():
def __init__(self):
# Define the functions supported by linking them to Python
# functions. These can be made elsewhere in the program,
# or imported (e.g., from numpy)
self.functions = {
'EXP': Function(numpy.exp),
'LOG': Function(numpy.log),
'SIN': Function(numpy.sin),
'COS': Function(numpy.cos),
'SQRT': Function(numpy.sqrt)
}
# Define the operators supported
# Link them to Python functions (here: from numpy)
self.operators = {
'PLUSS': Operator(numpy.add, 0),
'GANGE': Operator(numpy.multiply, 1),
'DELE': Operator(numpy.divide, 1),
'MINUS': Operator(numpy.subtract, 0)
}
# Define the output−queue . The parse text method fills this with RPN.
# The evaluate_output_queue method evaluates it
self.output_queue = Queue()
self.input_queue = Queue()
def evaluate_output_queue(self):
if not isinstance(self.output_queue.peek(),
Function) and not isinstance(
self.output_queue.peek(), Operator):
raise TypeError("This is not RPN")
def RSAcalculation(self):
sta = Stack()
size = self.output_queue.size()
for i in range(0, size):
element = self.output_queue.pop()
if isinstance(element, numbers.Number):
sta.push(element)
elif isinstance(element, Function):
number = sta.pop()
sta.push(element.execute(number))
else: #element er operator
number2 = sta.pop()
number1 = sta.pop()
sta.push(element.execute(number1, number2))
return sta.pop()
def to_RPN(self):
op_stack = Stack()
size_input = self.input_queue.size()
for i in range(0, size_input):
element = self.input_queue.peek()
if isinstance(element, numbers.Number):
self.output_queue.push(self.input_queue.pop())
elif isinstance(element, Function):
op_stack.push(self.input_queue.pop())
elif element == "(":
op_stack.push(self.input_queue.pop())
elif element == ")":
el = op_stack.peek()
while el != "(":
self.output_queue.push(op_stack.pop())
el = op_stack.peek()
op_stack.pop()
self.input_queue.pop()
elif isinstance(element, Operator):
if not op_stack.is_empty():
el = op_stack.peek()
while (isinstance(el, Operator)
and el.strength >= element.strength) or isinstance(
el, Function):
self.output_queue.push(op_stack.pop())
if op_stack.is_empty():
break
el = op_stack.peek()
op_stack.push(self.input_queue.pop())
size_stack = op_stack.size()
for i in range(0, size_stack):
self.output_queue.push(op_stack.pop())
def textparser(self, input_txt):
txt = input_txt.replace(" ", "").upper()
nums = "^[-0123456789.]+"
funcs = "|".join(["^" + func for func in self.functions])
ops = "|".join(["^" + op for op in self.operators])
parenths = r"^[\(\)]"
while txt != "":
check = re.search(nums, txt)
if check is not None:
txt = self.sub_string(txt, check.end)
self.input_queue.push(float(check.group(0)))
check = re.search(funcs, txt)
if check is not None:
txt = self.sub_string(txt, check.end)
self.input_queue.push(self.functions[check.group(0)])
check = re.search(ops, txt)
if check is not None:
txt = self.sub_string(txt, check.end)
self.input_queue.push(self.operators[check.group(0)])
check = re.search(parenths, txt)
if check is not None:
txt = self.sub_string(txt, check.end)
self.input_queue.push(check.group(0))
def sub_string(self, string, end):
if len(string) - 1 < end(0):
return ""
return string[end(0):]
def calculate_expression(self, txt):
self.textparser(txt)
self.to_RPN()
return self.RSAcalculation()
