This article discusses the application of arrays briefly. Arrays play a major role in the data structure. If you want to master data structure then master arrays first. Let’s get started!
In the era of modern computers, we need to process a huge amount of data. For this purpose data structure comes into the picture. Arrays are one of the ways to store data in the data structure. Let’s discuss even more in detail about the application of arrays.
The collection of elements of the same data type is an array. It has a fixed size(length). An index value helps in accessing the array elements. Elements can’t be different types and the index value can’t be a string.
The data structure is a way of organizing data. The reason for organizing data is to use it effectively.
Need for array:
Suppose we need to process a large amount of data in a continuous fashion, we use array. The main advantage of the array is that it stores data in a continuous manner. When we create two variables in any programming language the variable resides in any place in memory. Let’s see the example below.
Suppose we create two variables ‘a’ and ‘b’ of int type. They are stored in random places in memory say 209 and 809. This is how it looks like.
But this is not the case in the array. They are stored in a continuous manner. Let’s say we create an array of int type named ‘a’ of size 6. The memory location would look like the below image.
Need for data structure
The data structure in computer science means storing data effectively and fetching it whenever needed. The data structure may or may not have a relationship between the data present. ADT (Abstract data type )uses data structure as its basis.
Data structures are used for different applications. For example, consider the DMBS(Data Base Management System). We know that it is a way of storing, retrieving, manipulating data. The basis is once again data structure. They are used for storing and retrieval in both main and secondary memory. Many programming languages focus on data structure as the key to software development. The data structure is an important part of today’s era of mass data.
There are various kinds of arrays. The most predominant ones are the one-dimensional and multi-dimensional arrays. Other kinds of arrays are
- Jagged array
- Parallel array
- Bit array
- Dynamic array
Let’s see a brief explanation of some of the types.
This is nothing but the simple array we discussed above. The array can be of any type.
//declaration of single dimension array //array of int type and size 10 int a;
This is more like a matrix. We need to keep track of a row and a column. This also can be of any type. See the picture below to understand clearly.
//declaration of multidimensional array //array is size 2X2 int a
Here row and column serves as the index number.
By our example a11= 45, a12=0 and a21=12,a22=56. The element index represent the row and column number.
Dynamic array is also known by the names growable array, resizable array, mutable array, array access in a random way. This array can be expanded based on the user’s needs. During the run time of the program alone, we will know the size of the array. In C++ Dynamic array refers to Vector.
A group of parallel arrays is an implicit way of defining a data structure. It uses multiple arrays to represent a singular array of records. It keeps each separate array for a separate field of the record
The ragged array is another name for this. This array is an array of arrays such that member arrays can be of different arrays. To be short, the length of each array index can vary. The jagged array can also be combined with the multi-dimensional array.
This is an array data structure that stores bits. It implements a simple data structure. It is also called by names as bit set, bit vector, bit string, or bit map.
APPLICATION OF ARRAYS:
The array comes under linear data structure type. The linear type also contains stack and queue. These other types can also be operated in an array manner and in a linked list manner. Now let’s discuss the array operating manner of stack and queue. This is one of the applications of arrays in the data structure. Arrays also implement hash tables, strings, deques.
Stack in the programming world is similar to the real world example. Let’s compare the real-world example. Let’s say we have a pile of books or plates. What about their arrangement? The books or the plates are arranged on top of the top. In other words, they are arranged one over the other. This is how exactly a stack works in a programming world also.
For our convince the stack acts as the ‘over the top model’. But when a computer stores the values, it stores only as a normal array of single dimension and the index values is used to look like a stack.
An index named top is assigned 0 at first and as the values are added the top value is incremented. In this way the computer assumes a normal array to be a stack. The various operation can be done in the stack such as push, pop, etc. These are done by changing the index value accordingly.
We all are familiar with the word ‘queue’. The queue in the data structure also works in a similar fashion. The idea of the queue is that the person who enters into a line will quit the line first after his/her work is over. We do the exact in the data structure. The element which first enters the array first goes out of the array.
The operation of the queue is ‘enqueue’ and ‘dequeue’. Enqueue is nothing entering the elements in the array. And dequeue is removing elements from the array. For doing the operations, we use two indexes namely ‘front’ and ‘rear’.
‘Front’ is the first index and ‘rear’ is the last index. Elements enter the queue at the back. Removing elements takes place at the front. Always remember, the front index value is made to decrement.
Real time application of arrays
- We use applications such as MySQL and MongoDB. Ever wondered how the values compared and processed? Well, it uses arrays for back end comparison.
- In fast growing world as of today, now computers can recognize people and other similar patterns, How is this possible? This is image processing technique. In image processing, an image is an array. It uses 2D array. RGB image is n *n*3 array
- Modern computer uses speech processing where each speech signal is an array of signal amplitudes.
- We saw that stack is an application of array and in embedded system uses stack for storing intermediate results.
- Recording must be noise removed. To remove noise, we use filter which is an array.
- Play-fair cipher uses 2d array for encryption. It is one of the oldest methods.
- Every string we write, read area arrays. Many array of strings combine to form a sentence.
- A common example we all known is question paper. It consists of array of many numbered questions. Also if the answer script contains some bulleted points, they are also arrays.
- The number list or the contacts we have in our phone are arrays.
- We listen to music and have our own playlist. The playlist is also an array.
- Arrays are used in early function testing for accessing information.
Other application of arrays
Arrays are helpful in determining the control flow of the program. It is also a substitute for multiple If statements. One or more arrays servers the programs for allocation of dynamic memory. Arrays are simple and more space-efficient than other data structures.
We will now see the efficiency of the arrays we use in the data structure. Storing and selecting an element in the array takes constant time. This is when we get the worst-case scenario. Worst case scenario is nothing but when an element needed is present at the last index of the array.
The time complexity of an array of size n is O(n). This is linear. The number of cache misses is very less in the array than other data structures. This is because the array uses a continuous memory allocation system.
As far as memory concerns, the array is a compact storage one. Array occupies less space than a single variable stored. This is because array elements can make up a single word. ‘Packed array’ uses this technique. The dynamic array has a time complexity of reserve line 0(n). Dynamic arrays are very efficient.
- Array size is fixed. It is not possible to change the array size.
- We can store elements of the same data type
- The array length must be known before handed.
- Insertion and deletion of in-between are difficult.
- Wastage of storage: If elements are less, there is a wastage of memory.
Arrays play an important in the data structure for processing data. So it is important that you learn and understand the concept and application of arrays in a thorough manner. Hope now you understand the application of arrays in a clear way through the basics of course. Never stop learning and happy coding!