PYTHON

access list items in python

#Negative indexing means start from the end

-1 refers to the last item, -2 refers to the second last item etc.

thislist = ["apple", "banana", "cherry"]
print(thislist[-1])

#Outputt: cherry

Access item in a list of lists

>>> list1 = [[10,13,17],[3,5,1],[13,11,12]]
>>> list1[0][2]
17

how to access items in a list

list_example = ["python","ruby","java","javascript","c#","css","html"]
print(list_example[3])#javascript
print(list_example[0])#python
print(list_example[6])#html
print(list_example[0:3])

access element from list python

list1 = [1,2,3,4,5]
for i in list1:
  print(i)

accessing list elements in python

#In Python, we call the location of an element in a list its index.

###Python lists are zero-indexed. This means that the first element 
in a list has index 0, rather than 1.###

#Below is an example of this 
calls = ["Juan", "Zofia", "Amare", "Ezio", "Ananya"]
 #Where 
  Element	Index
  "Juan"	 0
  "Zofia"	 1
  "Amare"	 2
  "Ezio"	 3
  "Ananya"	 4
  
###so if we want to call out the 3rd element from the list,
our code would look like this###

print(calls[3])

#this will print out the following:
Amare


#THE BELOW INFO IS VERY IMPORTANT TO NOTE 
When accessing elements of a list, you must use an int as the index. 
If you use a float, you will get an error. 
This can be especially tricky when using division. 

For example print(calls[4/2]) will result in an error, 
because 4/2 gets evaluated to the float 2.0.

To solve this problem, you can force the result of your division to be 
an int by using the int() function. 

int() takes a number and cuts off the decimal point. 
For example, int(5.9) and int(5.0) will both become 5. 
Therefore, calls[int(4/2)] will result in the same value as calls[2], 
whereas calls[4/2] will result in an error.

Accessing Values in Lists

#!/usr/bin/python

list1 = ['physics', 'chemistry', 1997, 2000];
list2 = [1, 2, 3, 4, 5, 6, 7 ];
print "list1[0]: ", list1[0]
print "list2[1:5]: ", list2[1:5]