In [19]:
# Decomposition
# Abstraction

def sum_func(a, b):
  """ docstring
  This function returns the sum of two numbers
  Input: a, b
  Output: a + b
  """
  print(a + b)
  result = a + b
  return result, a, b

a,*b = sum_func(1, 2)
print(a,b)
type(a)
sum_func(1,b=2)

3
3 [1, 2]
3
Out[19]:
(3, 1, 2)
In [6]:
def blank_func():
  pass
In [17]:
def is_even(num):
  if num % 2 == 0:
    return True
  else:
    return False

is_even(num=2)
Out[17]:
True
In [29]:
# default parameter value
def sum_func(a=1, b=2):
  """ docstring
  This function returns the sum of two numbers
  Input: a, b
  Output: a + b
  """
  result = a + b
  return result

print(sum_func(3,b=2.4))
print(sum_func(3,2.4))
print(sum_func(a=3,b=2.4))

5.4
5.4
5.4

function is variable¶

In [30]:
f1 = sum_func
f1(1,2)
Out[30]:
3
In [33]:
x = -5
abs(x)
float(x)
L = [abs, float]
# [f(x) for f in L]
for f in L:
  print(f(x))

5
-5.0
In [36]:
def calculator(x,y,op):
  return op(x,y)

def add(x,y):
  return x + y

def sub(x,y):
  return x - y

calculator(1,2,add)
calculator(1,2,sub)
Out[36]:
-1
In [46]:
# iterable
x = range(5)
for x in x:
  print(x)
print(x)

0
1
2
3
4
4
In [48]:
x = range(5)
y = [print(x) for x in x]

0
1
2
3
4
Lambda function¶
In [41]:
x = lambda a,b: a + b
x(1,2)
Out[41]:
3
Variable scope¶
In [43]:
def my_func(x):
  a = 5
  return x * a

a = 4 # available from the function
my_func(4)
print(a)

4
In [51]:
def my_func(x):
  a += 5
  return x * a

a = 4 # available from the function
my_func(4)
print(a)

---------------------------------------------------------------------------
UnboundLocalError                         Traceback (most recent call last)
<ipython-input-51-67f4042c756d> in <cell line: 6>()
      4 
      5 a = 4 # available from the function
----> 6 my_func(4)
      7 print(a)

<ipython-input-51-67f4042c756d> in my_func(x)
      1 def my_func(x):
----> 2   a += 5
      3   return x * a
      4 
      5 a = 4 # available from the function

UnboundLocalError: local variable 'a' referenced before assignment
In [52]:
L = ['a', 'b', 'c']
def my_func(L):
  L.append('d')


my_func(L)
print(L)

['a', 'b', 'c', 'd']
In [56]:
# function that returns function
def myfunc(n):
  return lambda a : a * n

mydoubler = myfunc(3)

print(mydoubler(11))
print(mydoubler(22))
myfunc(2)(11)

33
66
Out[56]:
22
In [58]:
def make_cylinder_volume_func(r):
    def volume(h):
        return 3.14 * r * r * h
    return volume

volume_func = make_cylinder_volume_func(2)
volume_func(3)
Out[58]:
37.68
In [59]:
type(volume_func)
Out[59]:
function
In [60]:
volume_func
Out[60]:
make_cylinder_volume_func.<locals>.volume
def volume(h)
/content/<ipython-input-58-a4a9000247ad><no docstring>