class Stack:
"""An implementation of the typical stack data structure"""
def __init__(self, *args):
self.storage = Vector()
if len(args) != 0:
for item in args:
self.storage.append(item)
def clear(self):
"""Clears the entire contents of the stack"""
self.storage = Vector()
def is_emtpy(self):
return self.is_emtpy
@property
def is_empty(self):
if len(self.storage) == 0:
return True
else:
return False
def push(self, item):
"""Adds an item to the top of the stack"""
self.storage.append(item)
def pop(self):
"""Removes an item from the top of the stack"""
self.storage.erase_rear()
def top(self):
"""Returns the item at the top of the stack"""
return self.storage.back()
class Stack:
"""An implementation of the typical stack data structure"""
def __init__(self, *args):
self.storage = Vector()
if len(args) != 0:
for item in args:
self.storage.append(item)
def clear(self):
"""Clears the entire contents of the stack"""
self.storage = Vector()
def is_emtpy(self):
return self.is_emtpy
@property
def is_empty(self):
if len(self.storage) == 0:
return True
else:
return False
def push(self, item):
"""Adds an item to the top of the stack"""
self.storage.append(item)
def pop(self):
"""Removes an item from the top of the stack"""
self.storage.erase_rear()
def top(self):
"""Returns the item at the top of the stack"""
return self.storage.back()
def main(argv):
input_file = ""
output_file = ""
# First we attempt to get the options from the command line
try:
options, args = getopt.getopt(argv, "i:o:h")
except getopt.GetoptError:
print(
"""Call via `python poly_calc.py -i <input_file> -o <output_file>`\n
Use `python poly_calc.py -h` for help""")
# exit status 2 for command line error
sys.exit(2)
# Now we check what options were entered and act appropriately
for option, argument in options:
if option == "-h":
print("Call the script using:")
print(" python poly_calc.py -i <input_file> -o <output_file>")
print("The following flags are used:")
print(" -i must be by the input file name")
print(" -o can be followed by the output file name if desired")
if option == "-i":
input_file = argument
if option == "-o":
output_file = argument
# Ensure that there is input data
if input_file == "":
print("An input file must be specified")
else:
data = Vector() # Holds all of the lines out of the input file
stack = Stack() # Used to store the Polynomials and perform operations
# Read all of the lines out of the file
with open(input_file) as f:
for line in f:
data.append(line.strip())
for line in data:
if line == "+":
p1 = stack.top()
stack.pop()
p2 = stack.top()
stack.pop()
stack.push(p1 + p2)
elif line == "-":
p1 = stack.top()
stack.pop()
p2 = stack.top()
stack.pop()
stack.push(p1 - p2)
elif line == "*":
p1 = stack.top()
stack.pop()
p2 = stack.top()
stack.pop()
stack.push(p1 * p2)
else:
stack.push(Polynomial(line))
if output_file != "":
with open(output_file, 'w+') as f:
print(stack.top(), file=f)
else:
print(stack.top())
def main(argv):
input_file = ""
output_file = ""
# First we attempt to get the options from the command line
try:
options, args = getopt.getopt(argv, "i:o:h")
except getopt.GetoptError:
print("""Call via `python poly_calc.py -i <input_file> -o <output_file>`\n
Use `python poly_calc.py -h` for help""")
# exit status 2 for command line error
sys.exit(2)
# Now we check what options were entered and act appropriately
for option, argument in options:
if option == "-h":
print("Call the script using:")
print(" python poly_calc.py -i <input_file> -o <output_file>")
print("The following flags are used:")
print(" -i must be by the input file name")
print(" -o can be followed by the output file name if desired")
if option == "-i":
input_file = argument
if option == "-o":
output_file = argument
# Ensure that there is input data
if input_file == "":
print("An input file must be specified")
else:
data = Vector() # Holds all of the lines out of the input file
stack = Stack() # Used to store the Polynomials and perform operations
# Read all of the lines out of the file
with open(input_file) as f:
for line in f:
data.append(line.strip())
for line in data:
if line == "+":
p1 = stack.top()
stack.pop()
p2 = stack.top()
stack.pop()
stack.push(p1 + p2)
elif line == "-":
p1 = stack.top()
stack.pop()
p2 = stack.top()
stack.pop()
stack.push(p1 - p2)
elif line == "*":
p1 = stack.top()
stack.pop()
p2 = stack.top()
stack.pop()
stack.push(p1 * p2)
else:
stack.push(Polynomial(line))
if output_file != "":
with open(output_file, 'w+') as f:
print(stack.top(), file=f)
else:
print(stack.top())
def __add__(self, other):
"""Overloaded addition operator"""
temp = Vector()
for term in self.terms:
temp.append(term)
for term in other.terms:
temp.append(term)
new_poly = Polynomial()
new_poly.terms = temp
new_poly.combine_like_terms()
new_poly.sort_terms()
return new_poly
def __add__(self, other):
"""Overloaded addition operator"""
temp = Vector()
for term in self.terms:
temp.append(term)
for term in other.terms:
temp.append(term)
new_poly = Polynomial()
new_poly.terms = temp
new_poly.combine_like_terms()
new_poly.sort_terms()
return new_poly
def sort_terms(self):
"""Sorts the terms of the polynomial in O(n^2) time"""
temp = Vector()
for i in range(len(self.terms)):
max_exp = self.terms[0].exponent
max_exp_index = 0
for index, term in enumerate(self.terms):
if term.exponent > max_exp:
max_exp = term.exponent
max_exp_index = index
temp.append(self.terms[max_exp_index])
self.terms.erase(max_exp_index)
self.terms = temp
def __mul__(self, other):
"""Overloaded multiplication operator"""
temp = Vector()
for term in self.terms:
for item in other.terms:
new_coef = term.coef * item.coef
new_exp = term.exponent + item.exponent
temp.append(Term(new_coef, new_exp))
new_poly = Polynomial()
new_poly.terms = temp
new_poly.combine_like_terms()
new_poly.sort_terms()
return new_poly
def sort_terms(self):
"""Sorts the terms of the polynomial in O(n^2) time"""
temp = Vector()
for i in range(len(self.terms)):
max_exp = self.terms[0].exponent
max_exp_index = 0
for index, term in enumerate(self.terms):
if term.exponent > max_exp:
max_exp = term.exponent
max_exp_index = index
temp.append(self.terms[max_exp_index])
self.terms.erase(max_exp_index)
self.terms = temp
def __mul__(self, other):
"""Overloaded multiplication operator"""
temp = Vector()
for term in self.terms:
for item in other.terms:
new_coef = term.coef * item.coef
new_exp = term.exponent + item.exponent
temp.append(Term(new_coef, new_exp))
new_poly = Polynomial()
new_poly.terms = temp
new_poly.combine_like_terms()
new_poly.sort_terms()
return new_poly
def combine_like_terms(self):
max_exponent = 0
temp = Vector()
for term in self.terms:
max_exponent = max(max_exponent, term.exponent)
for exponent in range(max_exponent + 1):
new_coef = 0
for term in self.terms:
if term.exponent == exponent:
new_coef += term.coef
if (new_coef != 0):
temp.append(Term(new_coef, exponent))
self.terms = temp
self.sort_terms
def combine_like_terms(self):
max_exponent = 0
temp = Vector()
for term in self.terms:
max_exponent = max(max_exponent, term.exponent)
for exponent in range(max_exponent + 1):
new_coef = 0
for term in self.terms:
if term.exponent == exponent:
new_coef += term.coef
if (new_coef != 0):
temp.append(Term(new_coef, exponent))
self.terms = temp
self.sort_terms
