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List, Tuple and manipulation operation on Python Hunter's blog.


  

List in python are the most flexible datatype in python. Python list looks identical to c++ and java's array (elements separated by ',' coma) but unlike in features. Like c++ and java's array hold only similar types of elements (e.g String, int, double) and these programming languages have limitation to grow the size of their declared array at run time, array size has to defined at compile time (there could be some logic to decide the array size at run by getting the user's input but, after that it will be fixed, but it is not recommended) But Python list is slightly different from c++ and Java's array as it can grow it's size at run time and hold any multiple dataType in one single list (e.g string, int, char, Boolean....... all together in one list ).




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# Following are the ways to create list.


Python Hunter List Code Snippet(img)

Output:-

---------------------- Source Code Starts --------------------
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#Note:- Copy paste the code but make sure the indention.
myList = list('PranSukh') # empty list
#it will break down each character into separate elements, check the output.
print(myList)
myList = ["List","without","list_Object",'str','data','type','PythonHuter','''it's''',"Number",1] # new assignment
myList = list(range(1,10)) # new assignment
for i in range(len(myList)):
    print ("At Index ",i,myList[i],", and type is ",type(myList[i]))
print(myList)

print("*"*20) # hope You Know about this code, NO? then click here 
---------------------- Source Code Ends -------------------- 

print("*"*20) # hope You Know about this code, NO? then click here


#Nested List or complex list
Python Hunter Nested LIst pic

e.g. ------------- Nested List Source Code ---------------


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myList_1 = ["Hello",'Followers',["This","is","Pran","Sukh",2,["further","sublist"]],["PythonHunter"]]

#length function...



len() is very tiny function but very helpful to ease up the things. it takes out the length of string, list and tuple. Length of string will be equivalent to number of characters it is holding (including white spaces) white spaces and length of list and tuple will be number of element it is carrying.


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myList_1 = ["Hello",'Followers',["This","is","Pran","Sukh",2,["further","sublist"]],["PythonHunter"]]
for i in range(len(myList_1)):
    print ("At Index ",i,myList_1[i],", and type is ",type(myList_1[i]))
print(myList_1[2][5][1])


Output:

How to get required data from nested list?
Lets have look at the picture to make lucid view what we actually need to do.


Explanation:- 
We have a list (root list as depicted in Red Color) and it has 3 elements and each element is type of list (nested list, as depicted in yellow Color) and further the each nested list ( yellow  ) has three elements E1, E2, E3. Now if we want to get element E2 from the last nested list then first of all we have to get the root list element at index 2, which will give us a nested list with three elements E1, E2, E3, now will get the element at index of nested list which will return the element value E2.
so the code will be print(rootList[2][1])

#Even more complex list, step by step.
Here we have nested list and we want to get the nested list element value "required_data".


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# even more complex lists

compList=[1,["inside",["moreInside",["everMoreInside",["Python","Hunter",["getOff","randomly","data","required_data"]]],4],3],"outer"]
print (compList[1]) # track execution, step one
print (compList[1][1])# track execution, step two
print (compList[1][1][1])# track execution, step three
print (compList[1][1][1][1])# track execution, step four
print (compList[1][1][1][1][2])# track execution, step five
print (compList[1][1][1][1][2][3])# Final Step
print ("*"*50)

Output:-





#Tree like structure of lists and geting data from particular location.


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#tree like structure of lists and geting data from particular location.
crapList=[ 
 [
  [
   [1,2,3,4,5],[7,8,9,10],[11,12,13,14,15],[16,17,18,19,20]
  ],
  [
   [1,2,3,4,5],[7,8,9,10],[11,12,13,14,15],[16,17,18,19,20]
  ],
  [
   [1,2,3,4,5],[7,8,9,10],[11,12,13,14,15],[16,17,18,19,20]
  ],
  [
   [1,2,3,4,5],[7,8,9,10],[11,12,13,14,15],[16,17,18,19,20]
  ]
 ],

 [
  [
   [1,2,3,4,5],[7,8,9,10],[11,12,13,14,15],[16,17,18,19,20]
  ],
  [
   [1,2,3,4,5],[7,8,9,10],[11,12,13,14,15],[16,17,18,19,20]
  ],
  [
   [1,2,3,4,5],[7,8,9,10],[11,12,13,14,15],[16,17,18,19,20]
  ],
  [
   [1,2,3,4,5],[7,8,9,10],[11,12,13,14,15],[16,17,18,19,20]
  ]
 ],
 
 [
  [
   [1,2,3,4,5],[7,8,9,10],[11,12,13,14,15],[16,17,18,19,20]
  ],
  [
   [1,2,3,4,5],[7,8,9,10],[11,12,13,14,15],[16,17,18,19,20]
  ],
  [
   [1,2,3,4,5],[7,8,9,10],[11,12,13,14,15],[16,17,18,19,20]
  ],
  [
   [1,2,3,4,5],[7,8,9,10],[11,"PythonHunter",13,14,15],[16,17,18,19,20]
  ]
 ],
 
 [
  [
   [1,2,3,4,5],[7,8,9,10],[11,12,13,14,15],[16,17,18,19,20]
  ],
  [
   [1,2,3,4,5],[7,8,9,10],[11,12,13,14,15],[16,17,18,19,20]
  ],
  [
   [1,2,3,4,5],[7,8,9,10],[11,12,13,14,15],[16,17,18,19,20]
  ],
  [
   [1,2,3,4,5],[7,8,9,10],[11,12,13,14,15],[16,17,18,19,20]
  ]
 ],
 
 
]

print(crapList[2][3][2][1])


Comments

  1. Developing a tutorial comprehensive enough so that even a non technical would love the python in first sight.

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