Array in Python example
Python array is a data structure, like list, that allow you to store multiple records of similar data type.
Like all other programming language, in python, we have array concept, syntax is almost same as JavaScript, but here we see many different ways to work with array, first let’s understand how to define an array in python.
there are different ways we can define an array in python.
Define array using range, which accept an integer as parameter.
array1 = [0 for i in range(5)] print(array1) # result # [0, 0, 0, 0, 0]
Create python array using combine variable.
width, height=(4,5) box = [width,height] print(box)
Define array with comma-separated values, this is most commonly used way of creating an array in all other language.
array2 = [0,1,2,3,4,5,6,7,8,9] print(array2)
Here is how we can define two-dimension array in python.
array3 =[array1,array2] print(array3) #result [[0, 0, 0, 0, 0], [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]]
We can also create python array using array method of array module, here is an example below how you can use arr.array() method.
import array as arr
abc = arr.array('d', [1.5, 2.4, 8.9])
print(abc)
Python array methods
Here are some built-in array methods in python we often use, while working with python array, we often add new element to array, remove item from array, check array length or count elements in array, clear all items from array, etc.
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append()Adds an item to an array, let's day we want to add another fruit in following fruit array.
fruits = ["Banana", "Apple", "Orange"] fruits.append("Cucumber") -
pop()Removes an item from an array, we also can use remove method to remove an element from array.
fruits = ["Banana", "Apple", "Orange", "Cucumber"] fruits.remove("Apple") fruits.pop(1) // removes second element. -
clear()Removes all items from an array, for example we want to remote all items from following array
fruitsArray = ["Banana", "Apple", "Orange", "Cucumber"] fruitsArray.clear() #now there wont be any elements in fruitsArray.
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copy()Returns a copy of an array, copy method will copy all the elements from specified array to a new array.
fruits = ["Banana", "Apple", "Orange", "Cucumber"] fruits2 = fruits.copy() now fruits2 will have all the elements as source array.
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reverse()Reverses the order of the array
fruits = ["Banana", "Apple", "Orange"] fruits.reverse() // result : "Orange" , "Apple", "Banana"
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count()Returns the number of elements in a list, for example if we want to find how many times we have number 5 in following number array.
numberArray = [5,6,8,7,3,5,9,1,4,5,3] count = numberArray.count(5) #how many times number 5 is in the numberArray.
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len()We can find length of an array using len method, the method returns how many element there in the array.
array4 = [0,1,2,3,4,5,6,7,8,9] n = len(array4)
There is another advanced library in python called NumPy, that provides many built-in functionality to work with array object, You may be interested in following posts.
