Question

DesignLab 1:
I'm hoping to help everyone that gets stuck on the labs by sharing the code that I have written. It is not the only way to solve a problem, and sorry for the lack of comments!! Hopefully you can follow along :)

Answer 1

def fib(n):
if n == 0:
return 1
else:
return n * fib(n-1)

Answer 2

class V2(object):
def __init__(self,x,y):
self.x = x
self.y = y
def __str__(self):
return "V2 - (%s, %s)" %(self.x,self.y)
def getX(self):
return self.x
def getY(self):
return self.y
def add(self,b):
x = self.x + b.getX()
y = self.y + b.getY()
return V2(x,y)
def __add__(self,b):
return self.add(b)
def mul(self, s):
x = self.x * s
y = self.y * s
return V2(x,y)
def __mul__(self,s):
return self.mul(s)

Answer 3

class Polynomial:
def __init__(self,l):
self.coef = l
def __str__(self):
output = ""
count = len(self.coef)
for coef in self.coef:
if count > 2:
output = output + str(coef) + "z**" + str(count-1) + " + "
elif count > 1:
output = output + str(coef) + "z" + " + "
else:
output = output + str(coef)
count -= 1
return output
def add(self,b):
l = []
i = 0
if len(self.coef) > len(b.coef):
diff = len(self.coef)-len(b.coef)
while i < len(self.coef):
if i >= diff:
l.append(self.coef[i]+b.coef[i-diff])
i += 1
else:
l.append(self.coef[i])
i += 1
else:
diff = len(b.coef)-len(self.coef)
while i < len(b.coef):
if i >= diff:
l.append(self.coef[i-diff]+b.coef[i])
i += 1
else:
l.append(b.coef[i])
i += 1
return Polynomial(l)
def __add__(self,b):
return self.add(b)
def val(self,value):
output = 0.0
count = len(self.coef) - 1
for coef in self.coef:
output = output + coef * (value ** count)
count -= 1
return output
def __call__(self,value):
return self.val(value)
def mul(self, b):
assert len(b.coef) == len(self.coef)
l = []
len_a = len(self.coef)
for i in range(len_a):
for j in range(len_a):
place = i + j
if place < (len(l)) and i > 0:
# print "if : i %s j %s" % (i,j)
# print "place : ", place
l[place] = l[place] + (self.coef[i]*b.coef[j])
# print "l : ", l
else:
# print "else : i %s j %s" % (i,j)
l.append(self.coef[i]*b.coef[j])
return Polynomial(l)
def __mul__(self,s):
return self.mul(s)
def roots(self):
roots = []
if len(self.coef) == 1:
roots.append(self.coef)
return roots
elif len(self.coef) == 2:
roots.append((self.coef[1]*(-1.0))/self.coef[0])
return roots
elif len(self.coef) == 3:
a = self.coef[0]
b = self.coef[1]
c = self.coef[2]
disc = b**2 - 4 * a * c
# Find Complex Root
if disc < 0:
real = (-1.0 * b) / (2 * a)
imaginary = ((-1.0*disc) ** (0.5)) / (2 * a)
roots.append( complex(real,imaginary) )
roots.append( complex(real,(-1.0 * imaginary)) )
return roots
# Find Normal Root
else:
roots.append( ((-1.0*b) + ( disc ** (0.5) ))/( 2 * a) )
roots.append( ((-1.0*b) - ( disc ** (0.5) ))/( 2 * a) )
return roots
elif len(self.coef) > 3:
return "Order to high"