Environment setup: Python and Jupyter

Variables: Numbers, String, Tuple, List, Dictionary

Basic operators: Arithmetic and Boolean operators

Control flow: if/else, for, while, pass, break, continue

List: access, update, del, len(), + , in, for, slicing, append(), insert(), pop(), remove()

Dictionary: access, update, del, in

Function: function definition, pass by reference, keyword argument, default argument, lambda

map reduce filter

Module: from, import, reload(), package has init.py, init and str

I/O: raw_input(), input(), open(), close(), write(), read(), rename(), remove(), mkdir(), chdir(), rmdir()

Pass by value, Pass by reference

Date/time: local time and time zone, pytz module

Variables: Numbers, String, Tuple, List, Dictionary



In [2]:

    
x=1
print x



In [3]:

    
type(x)









    Out[3]:





int



In [7]:

    
x.conjugate()









    Out[7]:





1



In [9]:

    
type(1+2j)









    Out[9]:





complex



In [10]:

    
z=1+2j
print z









    



(1+2j)



In [11]:

    
(1,2)









    Out[11]:





(1, 2)



In [12]:

    
t=(1,2,"text")



In [13]:

    
t









    Out[13]:





(1, 2, 'text')



In [15]:

    
t









    Out[15]:





(1, 2, 'text')



In [16]:

    
def foo():
    return (1,2)
x,y=foo()



In [18]:

    
print x
print y

1
2



In [27]:

    
def swap(x,y):
    return (y,x)

x=1;y=2
print "{0:d} {1:d}".format(x,y)
x,y=swap(x,y)
print "{:f} {:f}".format(x,y)









    



1 2
2.000000 1.000000



In [29]:

    
dir(1)









    Out[29]:





['__abs__',
 '__add__',
 '__and__',
 '__class__',
 '__cmp__',
 '__coerce__',
 '__delattr__',
 '__div__',
 '__divmod__',
 '__doc__',
 '__float__',
 '__floordiv__',
 '__format__',
 '__getattribute__',
 '__getnewargs__',
 '__hash__',
 '__hex__',
 '__index__',
 '__init__',
 '__int__',
 '__invert__',
 '__long__',
 '__lshift__',
 '__mod__',
 '__mul__',
 '__neg__',
 '__new__',
 '__nonzero__',
 '__oct__',
 '__or__',
 '__pos__',
 '__pow__',
 '__radd__',
 '__rand__',
 '__rdiv__',
 '__rdivmod__',
 '__reduce__',
 '__reduce_ex__',
 '__repr__',
 '__rfloordiv__',
 '__rlshift__',
 '__rmod__',
 '__rmul__',
 '__ror__',
 '__rpow__',
 '__rrshift__',
 '__rshift__',
 '__rsub__',
 '__rtruediv__',
 '__rxor__',
 '__setattr__',
 '__sizeof__',
 '__str__',
 '__sub__',
 '__subclasshook__',
 '__truediv__',
 '__trunc__',
 '__xor__',
 'bit_length',
 'conjugate',
 'denominator',
 'imag',
 'numerator',
 'real']



In [30]:

    
x=[]



In [31]:

    
x.append("text")



In [32]:

    
x









    Out[32]:





['text']



In [33]:

    
x.append(1)



In [34]:

    
x.pop()









    Out[34]:





1



In [35]:

    
x.append([1,2,3])



In [36]:

    
x









    Out[36]:





['text', [1, 2, 3]]



In [37]:

    
x.append(2)



In [38]:

    
x









    Out[38]:





['text', [1, 2, 3], 2]



In [40]:

    
print x[0]
print x[-2]









    



text
[1, 2, 3]



In [41]:

    
x.pop(-2)









    Out[41]:





[1, 2, 3]



In [42]:

    
x









    Out[42]:





['text', 2]



In [56]:

    
%%timeit -n10
x=[]
for i in range(100000):
    x.append(2*i+1)









    



10 loops, best of 3: 41.9 ms per loop



In [55]:

    
%%timeit -n10
x=[]
for i in xrange(100000):
    x.append(2*i+1)









    



10 loops, best of 3: 39.1 ms per loop



In [47]:

    
range(10)









    Out[47]:





[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]



In [59]:

    
y=[2*i+1 for i in xrange(10)]
print y









    



[1, 3, 5, 7, 9, 11, 13, 15, 17, 19]



In [61]:

    
type({})









    Out[61]:





dict



In [62]:

    
x={"key":"value","foo":"bar"}
print x









    



{'foo': 'bar', 'key': 'value'}



In [67]:

    
key="key1"
if key in x:
    print x[key]



In [68]:

    
y={ i:i*i for i in xrange(10)}



In [69]:

    
y









    Out[69]:





{0: 0, 1: 1, 2: 4, 3: 9, 4: 16, 5: 25, 6: 36, 7: 49, 8: 64, 9: 81}



In [75]:

    
z=[v for (k,v) in y.iteritems()]
print z









    



[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]

if/else, for, while, pass, break, continue



In [80]:

    
p=[]
for i in xrange(2,100):
    isprime=1
    for j in p:
        if(i%j==0):
            isprime=0
            break
    if isprime:
        p.append(i)
        
print p









    



[2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97]



In [82]:

    
for i in xrange(10):
    pass



In [4]:

    
i=10
while i>0:
    i=i-1
    print i



In [9]:

    
x=['text',"str",''' Hello World\\n ''']
print x









    



['text', 'str', ' Hello World\\n ']

List: access, update, del, len(), + , in, for, slicing, append(), insert(), pop(), remove()



In [13]:

    
x=['a','b','c']
#access
print x[0]
#update
x[0]='d'
print x
print "size of x%d is"%len(x)









    



a
['d', 'b', 'c']
size of x3 is



In [16]:

    
y=['x','y','z']
z=x+y
gamma=y+x
print z
print gamma









    



['d', 'b', 'c', 'x', 'y', 'z']
['x', 'y', 'z', 'd', 'b', 'c']



In [18]:

    
print 'a' in x









    



False



In [21]:

    
print y
y.remove('y')# remove by vavlue
print y









    



['x', 'y', 'z']
['x', 'z']



In [22]:

    
print y
y.pop(0)# remove by index
print y









    



['x', 'z']
['z']



In [23]:

    
y.insert(0,'x')
y.insert(1,'y')
print y









    



['x', 'y', 'z']



In [31]:

    
x=[i*i for i in xrange(10)]
print x









    



[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]



In [32]:

    
x[:3]









    Out[32]:





[0, 1, 4]



In [33]:

    
x[-3:]









    Out[33]:





[49, 64, 81]



In [36]:

    
x[-1:]









    Out[36]:





[81]



In [38]:

    
x[3:-3]









    Out[38]:





[9, 16, 25, 36]



In [40]:

    
x[1:6]









    Out[40]:





[1, 4, 9, 16, 25]



In [54]:

    
x[::2]









    Out[54]:





[0, 4, 16, 36, 64]



In [61]:

    
print x
x.reverse()
print x









    



[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
[81, 64, 49, 36, 25, 16, 9, 4, 1, 0]



In [62]:

    
print x
print x[::-1]
print x









    



[81, 64, 49, 36, 25, 16, 9, 4, 1, 0]
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
[81, 64, 49, 36, 25, 16, 9, 4, 1, 0]

Dictionary: access, update, del, in



In [63]:

    
x={}



In [65]:

    
x={'key':'value'}



In [67]:

    
x['foo']='bar'



In [68]:

    
x









    Out[68]:





{'foo': 'bar', 'key': 'value'}



In [69]:

    
x['foo']='Hello'



In [70]:

    
x









    Out[70]:





{'foo': 'Hello', 'key': 'value'}



In [71]:

    
x['m']=123



In [77]:

    
x['foo','key']









    



---------------------------------------------------------------------------
KeyError                                  Traceback (most recent call last)
<ipython-input-77-ce049a4a288b> in <module>()
----> 1 x['foo','key']

KeyError: ('foo', 'key')



In [76]:

    
keys=['foo','key']
[x[k] for k in keys]









    Out[76]:





['Hello', 'value']



In [78]:

    
print x
del x
print x









    



{'foo': 'Hello', 'm': 123, 'key': 'value'}






    



---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
<ipython-input-78-28797b7c5a91> in <module>()
      1 print x
      2 del x
----> 3 print x

NameError: name 'x' is not defined

Function: function definition, pass by reference, keyword argument, default argument, lambda

a built-in immutable type: str, int, long, bool, float, tuple



In [80]:

    
def foo(x):
    x=x+1
    y=2*x
    return y
print foo(3)



In [81]:

    
x=3
print foo(x)
print x

8
3



In [84]:

    
def bar(x=[]):
    x.append(7)
    print "in loop: {}".format(x)

x=[1,2,3]
print x
bar(x)
print x









    



[1, 2, 3]
in loop: [1, 2, 3, 7]
[1, 2, 3, 7]



In [85]:

    
def func(x=0,y=0,z=0):#defualt input argument
    return x*100+y*10+z

func(1,2)









    Out[85]:





120



In [87]:

    
func(y=2,z=3,x=1)#keyword input argument









    Out[87]:





123



In [88]:

    
f=func



In [89]:

    
f(y=2)









    Out[89]:





20



In [93]:

    
distance=[13,500,1370]#meter
def meter2Kilometer(d):
    return d/1000.0;



In [94]:

    
meter2Kilometer(distance)









    



---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-94-0289b1544d80> in <module>()
----> 1 meter2Kilometer(distance)

<ipython-input-93-26f4f625c2ba> in meter2Kilometer(d)
      1 distance=[13,500,1370]#meter
      2 def meter2Kilometer(d):
----> 3     return d/1000.0;

TypeError: unsupported operand type(s) for /: 'list' and 'float'



In [95]:

    
[meter2Kilometer(d) for d in distance]









    Out[95]:





[0.013, 0.5, 1.37]



In [98]:

    
d2 = map(meter2Kilometer,distance)
print d2









    



[0.013, 0.5, 1.37]



In [101]:

    
d3 = map(lambda x: x/1000.0,distance)
print d3









    



[0.013, 0.5, 1.37]



In [105]:

    
distance=[13,500,1370]#meter
time=[1,10,100]
d3 = map(lambda s,t: s/float(t)*3.6, distance,time )
print d3









    



[46.800000000000004, 180.0, 49.32]



In [108]:

    
d4=filter(lambda s: s<1000, distance)
print d4



In [110]:

    
total_distance=reduce(lambda i,j : i+j, distance)
total_distance









    Out[110]:





1883



In [129]:

    
import numpy as np
x=np.arange(101)
print x









    



[  0   1   2   3   4   5   6   7   8   9  10  11  12  13  14  15  16  17
  18  19  20  21  22  23  24  25  26  27  28  29  30  31  32  33  34  35
  36  37  38  39  40  41  42  43  44  45  46  47  48  49  50  51  52  53
  54  55  56  57  58  59  60  61  62  63  64  65  66  67  68  69  70  71
  72  73  74  75  76  77  78  79  80  81  82  83  84  85  86  87  88  89
  90  91  92  93  94  95  96  97  98  99 100]



In [130]:

    
np.histogram(x,bins=[0,50,60,70,80,100])









    Out[130]:





(array([50, 10, 10, 10, 21], dtype=int64),
 array([  0,  50,  60,  70,  80, 100]))



In [131]:

    
print np.sort(x)









    



[  0   1   2   3   4   5   6   7   8   9  10  11  12  13  14  15  16  17
  18  19  20  21  22  23  24  25  26  27  28  29  30  31  32  33  34  35
  36  37  38  39  40  41  42  43  44  45  46  47  48  49  50  51  52  53
  54  55  56  57  58  59  60  61  62  63  64  65  66  67  68  69  70  71
  72  73  74  75  76  77  78  79  80  81  82  83  84  85  86  87  88  89
  90  91  92  93  94  95  96  97  98  99 100]

Module: class, from, import, reload(), package and init



In [138]:

    
class Obj:
    def __init__(self, _x, _y):
        self.x = _x
        self.y = _y
    
    def update(self, _x, _y):
        self.x += _x
        self.y += _y  
        
    def __str__(self):
        return "x:%d, y:%d"%(self.x,self.y)



In [141]:

    
a=Obj(5,7)#call __init__
print a#call __str__
a.update(1,2)#call update
print a









    



x:5, y:7
x:6, y:9



In [163]:

    
import sys
import os
path=os.getcwd()
path=os.path.join(path,'lib')
print path
sys.path.insert(0, path)
from Obj import Obj as ob









    



C:\Users\Wasit\Documents\GitHub\PythonDay\notebook\lib



In [166]:

    
b=ob(7,9)
print b
b.update(3,7)
print b









    



x:7, y:9
x:10, y:16



In [158]:

    
os.getcwd()









    Out[158]:





'C:\\Users\\Wasit\\Documents\\GitHub\\PythonDay\\notebook'



In [179]:

    
from mylib import mymodule as mm



In [180]:

    
mm=reload(mm)



In [182]:

    
print mm.Obj2(8,9)









    



x:8, y:9



In [ ]: