In [1]:

    

# breaking down a simple def into a lambda
def square(num):
    result = num**2
    return result


    

In [2]:

    

# shorten this a bit
def square(num):
    return num**2


    

In [3]:

    

def square(num): return num**2 # bad style, but works syntactically


    

In [4]:

    

square(3)


    

    
Out[4]:





9

In [8]:

    

square_2 = lambda num: num**2


    

In [10]:

    

square_2(4)


    

    
Out[10]:





16

In [12]:

    

# check if number is even
evens = lambda num: num % 2 == 0


    

In [14]:

    

evens(4)


    

    
Out[14]:





True

In [15]:

    

evens(5)


    

    
Out[15]:





False

In [16]:

    

comparison = lambda x,y: x > y


    

In [17]:

    

comparison(4, 5)


    

    
Out[17]:





False

In [18]:

    

comparison(2, 1)


    

    
Out[18]:





True

In [19]:

    

type(comparison)


    

    
Out[19]:





function

In [20]:

    

# grabs first character of a string
grab_first = lambda word: word[0]


    

In [21]:

    

grab_first("hello")


    

    
Out[21]:





'h'

In [22]:

    

# reverse string
reverse_s = lambda s: s[::-1]


    

In [23]:

    

reverse_s("hello, world!")


    

    
Out[23]:





'!dlrow ,olleh'

In [24]:

    

# add two numbers


    

In [25]:

    

adder = lambda x, y: x + y


    

In [26]:

    

adder(4, 5)


    

    
Out[26]:





9

In [28]:

    

adder("hello", "world!")


    

    
Out[28]:





'helloworld!'

In [29]:

    

adder(["hello"], ["world"])


    

    
Out[29]:





['hello', 'world']

In [30]:

    

# used primarily in this:
map()
filter()
reduce()


    

    




---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-30-2255bf60e608> in <module>()
----> 1 map()
      2 filter()

TypeError: map() requires at least two args

In [ ]: