What is data Structure?
A data Structure is the organization of data in computers memory or in a file.
Some examples of data structures are: array, stack, queue, link list, binary tree hash table, heap and graph. Data structures are often used to build databases. Typically, data structures are manipulated using various algorithms.
Based on the concept of Abstract data types (ADT), we define data structure by the following three components.
1. Operations: Specifications of external appearance of data structure.
2. Storage Structures: Organizations of data implemented in lower-level data structures.
3. Algorithms: Description on how to manipulate information in the storage structures to obtain the results defined for operations.
There are three levels of implementation of data structure which are:
1. The Abstract Level: The abstract (or logical) level is the specifications of the data structure the “What” but not “how”. At this level. The user or data structure designer is free think outside the bounds of anyone programming language.
2. Application Level: At the application or user level, the user is modeling real-life data in a specific context.
3. Implementation Level: The implementation level is where the model becomes compatible, executable code.
The data structure can only be accessed with defined operations. This set of operations is called interface and abstract data type is exported by the entity. An entity with the properties just described is called an abstract data type (ADT).
Abstract data type is characterized by the following Properties.
1. It exports a type.
2. It exports a set of operations. This set is called interface.
3. Operations of the interface are the one and only access mechanism to the type’s data structure.
4. Axioms and preconditions define the application domain of type.
1. Data: This part describes the structure of the data used in the ADT in an informal way.
2. Operations: This part describes valid operations for this ADT; hence, it describes its interface. We use special operation constructor to describe the actions which are to be performed once an entity of this ADT is created and destructed to describe the actions which are to be performed once an entity is destroyed.
A data Structure is the organization of data in computers memory or in a file.
Some examples of data structures are: array, stack, queue, link list, binary tree hash table, heap and graph. Data structures are often used to build databases. Typically, data structures are manipulated using various algorithms.
Based on the concept of Abstract data types (ADT), we define data structure by the following three components.
1. Operations: Specifications of external appearance of data structure.
2. Storage Structures: Organizations of data implemented in lower-level data structures.
3. Algorithms: Description on how to manipulate information in the storage structures to obtain the results defined for operations.
Implementation of Data Structure
There are three levels of implementation of data structure which are:
1. The Abstract Level: The abstract (or logical) level is the specifications of the data structure the “What” but not “how”. At this level. The user or data structure designer is free think outside the bounds of anyone programming language.
2. Application Level: At the application or user level, the user is modeling real-life data in a specific context.
3. Implementation Level: The implementation level is where the model becomes compatible, executable code.
Abstract data types
The data structure can only be accessed with defined operations. This set of operations is called interface and abstract data type is exported by the entity. An entity with the properties just described is called an abstract data type (ADT).
Properties of an abstract data type
1. It exports a type.
2. It exports a set of operations. This set is called interface.
3. Operations of the interface are the one and only access mechanism to the type’s data structure.
4. Axioms and preconditions define the application domain of type.
Parts of ADT description
2. Operations: This part describes valid operations for this ADT; hence, it describes its interface. We use special operation constructor to describe the actions which are to be performed once an entity of this ADT is created and destructed to describe the actions which are to be performed once an entity is destroyed.
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