Lists



In [1]:

    
m_list = [1,2,3]



In [2]:

    
m_list









    Out[2]:





[1, 2, 3]



In [3]:

    
m_list2 = ['potter', 1.23, 'v', 217]



In [4]:

    
m_list2









    Out[4]:





['potter', 1.23, 'v', 217]



In [5]:

    
len(m_list2)









    Out[5]:





4



In [6]:

    
m_list3 = ['one', 'two', 'three', 4, 5]



In [7]:

    
m_list3[0]









    Out[7]:





'one'



In [8]:

    
m_list3[3]









    Out[8]:





4



In [9]:

    
m_list3[1:]









    Out[9]:





['two', 'three', 4, 5]



In [10]:

    
m_list3[:4]









    Out[10]:





['one', 'two', 'three', 4]



In [11]:

    
'hello' + 'world'









    Out[11]:





'helloworld'



In [12]:

    
m_list + m_list2 + m_list3









    Out[12]:





[1, 2, 3, 'potter', 1.23, 'v', 217, 'one', 'two', 'three', 4, 5]



In [13]:

    
m_list3 + ['Vinay']









    Out[13]:





['one', 'two', 'three', 4, 5, 'Vinay']



In [14]:

    
m_list = m_list + m_list2



In [15]:

    
m_list









    Out[15]:





[1, 2, 3, 'potter', 1.23, 'v', 217]



In [17]:

    
m_list3 * 2









    Out[17]:





['one', 'two', 'three', 4, 5, 'one', 'two', 'three', 4, 5]



In [18]:

    
m_list3 * 3









    Out[18]:





['one',
 'two',
 'three',
 4,
 5,
 'one',
 'two',
 'three',
 4,
 5,
 'one',
 'two',
 'three',
 4,
 5]



In [19]:

    
m_list4 = [1,2,3]



In [20]:

    
m_list4.append('appendMe')



In [21]:

    
m_list4









    Out[21]:





[1, 2, 3, 'appendMe']



In [22]:

    
m_list4.append(2.0232)



In [23]:

    
m_list4









    Out[23]:





[1, 2, 3, 'appendMe', 2.0232]



In [26]:

    
m_list4.pop()









    Out[26]:





2.0232



In [27]:

    
m_list4









    Out[27]:





[1, 2, 3, 'appendMe']



In [28]:

    
m_list4.pop(2)









    Out[28]:





3



In [29]:

    
m_list4









    Out[29]:





[1, 2, 'appendMe']



In [30]:

    
m_list4[1]









    Out[30]:





2



In [31]:

    
m_list4[89]









    



---------------------------------------------------------------------------
IndexError                                Traceback (most recent call last)
<ipython-input-31-f9fe36636b0e> in <module>()
----> 1 m_list4[89]

IndexError: list index out of range



In [32]:

    
new_list = ['a', 'e', 'x', 'b', 'c']



In [33]:

    
new_list









    Out[33]:





['a', 'e', 'x', 'b', 'c']



In [35]:

    
new_list.reverse()



In [36]:

    
new_list









    Out[36]:





['c', 'b', 'x', 'e', 'a']



In [38]:

    
new_list.sort()



In [39]:

    
new_list









    Out[39]:





['a', 'b', 'c', 'e', 'x']



In [40]:

    
l_1 = [1,2.3]



In [41]:

    
l_2 = [4,5,6]



In [42]:

    
l_3 = [7,8,9]



In [43]:

    
matrix = [l_1, l_2, l_3]



In [44]:

    
matrix









    Out[44]:





[[1, 2.3], [4, 5, 6], [7, 8, 9]]



In [45]:

    
matrix[0]









    Out[45]:





[1, 2.3]



In [46]:

    
matrix[0][0]









    Out[46]:





1



In [47]:

    
matrix[2][2]









    Out[47]:





9



In [48]:

    
matrix[1][2]









    Out[48]:





6



In [52]:

    
# list comprehensions

first_col = [row[0] for row in matrix]



In [53]:

    
first_col









    Out[53]:





[1, 4, 7]



In [ ]:

Dictionaries



In [54]:

    
m_dict = {'key1':'value', 'key2':217}



In [55]:

    
m_dict









    Out[55]:





{'key1': 'value', 'key2': 217}



In [56]:

    
m_dict[0]









    



---------------------------------------------------------------------------
KeyError                                  Traceback (most recent call last)
<ipython-input-56-44652b751c13> in <module>()
----> 1 m_dict[0]

KeyError: 0



In [57]:

    
m_dict['key1']









    Out[57]:





'value'



In [58]:

    
m_dict['key2'] = m_dict['key2'] - 17



In [59]:

    
m_dict









    Out[59]:





{'key1': 'value', 'key2': 200}



In [60]:

    
# empty dictionary

d = {}



In [61]:

    
d









    Out[61]:





{}



In [62]:

    
# adding key:value pair to dictionary

d['animal'] = 'Phoenix'



In [63]:

    
d









    Out[63]:





{'animal': 'Phoenix'}



In [64]:

    
d['wizard'] = 'Potter'



In [65]:

    
d









    Out[65]:





{'animal': 'Phoenix', 'wizard': 'Potter'}



In [67]:

    
d2 = {'k1':{'nestkey':{'subnestkey': 'value'}}}



In [68]:

    
d2









    Out[68]:





{'k1': {'nestkey': {'subnestkey': 'value'}}}



In [72]:

    
d2['k1']









    Out[72]:





{'nestkey': {'subnestkey': 'value'}}



In [73]:

    
d2['k1']['nestkey']









    Out[73]:





{'subnestkey': 'value'}



In [74]:

    
d2['k1']['nestkey']['subnestkey']









    Out[74]:





'value'



In [75]:

    
d2['k1']['nestkey']['subnestkey'].upper()









    Out[75]:





'VALUE'



In [76]:

    
d3 = {}



In [77]:

    
d3['k1'] = 1



In [78]:

    
d3['k2'] = 2



In [79]:

    
d3['k3'] = 3



In [80]:

    
d3









    Out[80]:





{'k1': 1, 'k2': 2, 'k3': 3}



In [81]:

    
d3.keys()       # returns a list of all keys in the dict









    Out[81]:





['k3', 'k2', 'k1']



In [82]:

    
d3.values()     # returns a list of all values in the dict









    Out[82]:





[3, 2, 1]



In [84]:

    
d3.items()      # returns a list of tuples(key:value) n the dict









    Out[84]:





[('k3', 3), ('k2', 2), ('k1', 1)]



In [85]:

    
d3['k1'] = 0     # dictionaries are mutable



In [86]:

    
d3









    Out[86]:





{'k1': 0, 'k2': 2, 'k3': 3}



In [ ]:

Tuples



In [2]:

    
m_tuple = (1, 2, 3)



In [3]:

    
m_tuple









    Out[3]:





(1, 2, 3)



In [4]:

    
len(m_tuple)









    Out[4]:





3



In [5]:

    
m_tuple2 = ('one', 2)



In [6]:

    
m_tuple2









    Out[6]:





('one', 2)



In [8]:

    
m_tuple2[0]









    Out[8]:





'one'



In [9]:

    
m_tuple2[-1]









    Out[9]:





2



In [13]:

    
# returns the index of the input if that input exists inside the tuple
m_tuple2.index('one')









    Out[13]:





0



In [12]:

    
m_tuple2.index(2)









    Out[12]:





1



In [14]:

    
# returns the count of the input inside the tuple
m_tuple2.count('one')









    Out[14]:





1



In [15]:

    
m_tuple3 = (1, 1, 1, 2, 3, 2, 1, 3, 2, 1)



In [16]:

    
m_tuple3.count(1)









    Out[16]:





5



In [17]:

    
m_tuple3.count(2)









    Out[17]:





3



In [18]:

    
m_tuple3.count(3)









    Out[18]:





2



In [19]:

    
# tuples are immutable but lists are mutable

m_tuple3[0] = 123









    



---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-19-48c7ddc0d819> in <module>()
      1 # tuples are immutable but lists are mutable
      2 
----> 3 m_tuple3[0] = 123

TypeError: 'tuple' object does not support item assignment



In [ ]:

Files



In [23]:

    
pwd









    Out[23]:





u'/media/potter217/Saililashah/Projects/Lumos/Project_Python/py_bootcamp'



In [26]:

    
m_file = open('test.txt')



In [27]:

    
m_file









    Out[27]:





<open file 'test.txt', mode 'r' at 0x7f8ec8243810>



In [28]:

    
m_file.read()









    Out[28]:





'Hello Rustom Potter'



In [29]:

    
m_file.read()









    Out[29]:





''



In [31]:

    
m_file.seek(0)



In [32]:

    
m_file.read()









    Out[32]:





'Hello Rustom Potter'



In [33]:

    
m_file.read()









    Out[33]:





'\nNamaste!!'



In [34]:

    
m_file.read()









    Out[34]:





''



In [36]:

    
m_file.seek(0)



In [37]:

    
m_file.read()









    Out[37]:





'Hello Rustom Potter\nNamaste!!'



In [38]:

    
m_file.readline()









    Out[38]:





''



In [39]:

    
m_file.seek(0)



In [40]:

    
m_file.readline()









    Out[40]:





'Hello Rustom Potter\n'



In [41]:

    
m_file.seek(0)



In [42]:

    
m_file.readlines()









    Out[42]:





['Hello Rustom Potter\n', 'Namaste!!']



In [43]:

    
m_file.seek(1)



In [44]:

    
m_file.readlines()









    Out[44]:





['ello Rustom Potter\n', 'Namaste!!']



In [46]:

    
%%writefile newtest.txt
firstLine
second line









    



Writing newtest.txt



In [47]:

    
m_newtestFile = open('newtest.txt')



In [48]:

    
m_newtestFile.readlines()









    Out[48]:





['firstLine\n', 'second line']



In [49]:

    
ls









    



dataStructures.ipynb*  master/  newtest.txt*  objects.ipynb*  test.txt*



In [50]:

    
for line in open('newtest.txt'):
    print line









    



firstLine

second line



In [ ]:

Sets & Booleans



In [51]:

    
m_set = set()



In [52]:

    
m_set









    Out[52]:





set()



In [53]:

    
m_set.add(1)



In [54]:

    
m_set









    Out[54]:





{1}



In [55]:

    
m_set.add('123')



In [56]:

    
m_set









    Out[56]:





{1, '123'}



In [58]:

    
m_set.add(1)



In [59]:

    
m_set









    Out[59]:





{1, '123'}



In [60]:

    
m_listSET = [1,1,1,1,1,1,1, 2,2,2,2, 3,2,21,1]



In [61]:

    
m_listSET









    Out[61]:





[1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 2, 21, 1]



In [64]:

    
# contains only UNIQUE elements
set(m_listSET)









    Out[64]:





{1, 2, 3, 21}



In [65]:

    
# BOOLEANS



In [66]:

    
m_bool = True



In [67]:

    
m_bool









    Out[67]:





True



In [68]:

    
1  > 2









    Out[68]:





False



In [69]:

    
1 > -1









    Out[69]:





True



In [70]:

    
0 > 0









    Out[70]:





False



In [71]:

    
m_boolNone = None



In [72]:

    
# a Placeholder
m_none = None



In [73]:

    
m_none



In [74]:

    
m_none = 'Rustom'



In [75]:

    
m_none









    Out[75]:





'Rustom'



In [76]:

    
2**38









    Out[76]:





274877906944



In [ ]: