2.1.15

2D Arrays

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2D Arrays

A 2D array is the data structure which consists of an array of arrays.

2D Array

2D Array

A 2D array is a data structure where arrays are filled with other arrays.
This can be used to represent a 2D surface, or records.

Accessing elements

Accessing elements

To access an individual array, we can access the array as usual:
- array = my2DArray[4]
To access an individual element, we use this syntax:
- array[5][0]
This would get the first element of the sixth array.

Applications of 2D arrays

Applications of 2D arrays

2D arrays are often used to represent a 2D surface, for example a chess board:
- Each element of the 2D array could contain the chess piece in that location.
2D arrays can be used to represent a database:
- The outer array stores a collection of records.
- The inner arrays store a single record.

1

Computational Thinking & Algorithms

1.1

Computational Thinking

1.1.1Abstraction Thinking 1.1.2Decomposition Thinking 1.1.3Algorithmic Thinking

1.2

Algorithms

1.2.1Algorithms 1.2.2Pseudocode 1.2.3Flow Diagrams 1.2.4Logical Reasoning & Debugging 1.2.5Reading Algorithms 1.2.6Correcting Algorithms 1.2.7Complete the Algorithm 1.2.8Search Algorithms 1.2.9Linear Search 1.2.10Binary Search 1.2.11Sort Algorithms 1.2.12Bubble Sort 1.2.13Insertion Sort 1.2.14End of Topic Test - Algorithms

2

Programming

3

Hardware & Software

3.1

Hardware

3.1.1Elements of Computer Systems 3.1.2Central Processing Unit (CPU)3.1.3Registers of the Central Processing Unit (CPU)3.1.4Factors Affecting CPU Performance 3.1.5Fetch-Decode-Execute Cycle 3.1.6Binary Systems 3.1.7Logic Circuits 3.1.8Boolean Logic 3.1.9End of Topic Test - Logic

3.2

Software

3.2.1System Software

4

Data

4.1

Representing Data

4.1.1Binary 4.1.2Converting Binary & Hexadecimal 4.1.3Converting Denary & Hexadecimal 4.1.4Binary Arithmetic 4.1.5Representing Sound 4.1.6Representing Images 4.1.7Character Sets 4.1.8American Standard Code for Information Interchange 4.1.9Unicode 4.1.10End of Topic Test - Representation

5

The Internet

5.1

Networks

5.1.1Networks 5.1.2Geographical Classification of Networks 5.1.3What is the Internet?5.1.4The World Wide Web 5.1.5Uniform Resource Locators (URLs)5.1.6Web Hosting 5.1.7HTML 5.1.8Searching the World Wide Web 5.1.9Good Searching Tips 5.1.10Are You Looking at Reliable Information?

6

Online Safety & Security

6.1

Protecting Yourself Online

6.1.1Digital Footprints 6.1.2Leaving a Safe Online Footprint 6.1.3Online Safety 6.1.4Malware - Viruses 6.1.5Malware 6.1.6People Online 6.1.7Your Feelings 6.1.8Getting Help

6.2

Computing and the Law

6.2.1Data Protection Act (1998)6.2.2Computer Misuse Act (1990)6.2.3Freedom of Information Act (2000)6.2.4Plagiarism 6.2.5Copyright 6.2.6Copyright Designs and Patents Act (1988)6.2.7Creative Commons Licensing

Jump to other topics

1

Computational Thinking & Algorithms

1.1

Computational Thinking

1.1.1Abstraction Thinking 1.1.2Decomposition Thinking 1.1.3Algorithmic Thinking

1.2

Algorithms

1.2.1Algorithms 1.2.2Pseudocode 1.2.3Flow Diagrams 1.2.4Logical Reasoning & Debugging 1.2.5Reading Algorithms 1.2.6Correcting Algorithms 1.2.7Complete the Algorithm 1.2.8Search Algorithms 1.2.9Linear Search 1.2.10Binary Search 1.2.11Sort Algorithms 1.2.12Bubble Sort 1.2.13Insertion Sort 1.2.14End of Topic Test - Algorithms

2

Programming

3

Hardware & Software

3.1

Hardware

3.1.1Elements of Computer Systems 3.1.2Central Processing Unit (CPU)3.1.3Registers of the Central Processing Unit (CPU)3.1.4Factors Affecting CPU Performance 3.1.5Fetch-Decode-Execute Cycle 3.1.6Binary Systems 3.1.7Logic Circuits 3.1.8Boolean Logic 3.1.9End of Topic Test - Logic

3.2

Software

3.2.1System Software

4

Data

4.1

Representing Data

4.1.1Binary 4.1.2Converting Binary & Hexadecimal 4.1.3Converting Denary & Hexadecimal 4.1.4Binary Arithmetic 4.1.5Representing Sound 4.1.6Representing Images 4.1.7Character Sets 4.1.8American Standard Code for Information Interchange 4.1.9Unicode 4.1.10End of Topic Test - Representation

5

The Internet

5.1

Networks

5.1.1Networks 5.1.2Geographical Classification of Networks 5.1.3What is the Internet?5.1.4The World Wide Web 5.1.5Uniform Resource Locators (URLs)5.1.6Web Hosting 5.1.7HTML 5.1.8Searching the World Wide Web 5.1.9Good Searching Tips 5.1.10Are You Looking at Reliable Information?

6

Online Safety & Security

6.1

Protecting Yourself Online

6.1.1Digital Footprints 6.1.2Leaving a Safe Online Footprint 6.1.3Online Safety 6.1.4Malware - Viruses 6.1.5Malware 6.1.6People Online 6.1.7Your Feelings 6.1.8Getting Help

6.2

Computing and the Law

6.2.1Data Protection Act (1998)6.2.2Computer Misuse Act (1990)6.2.3Freedom of Information Act (2000)6.2.4Plagiarism 6.2.5Copyright 6.2.6Copyright Designs and Patents Act (1988)6.2.7Creative Commons Licensing

Practice questions on 2D Arrays

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1
What would the command "array[5][3] = 0" do to a 2D array?Multiple choice

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