IB Computer Science Topic B2.5.1 Constructing Code to Perform File-processing Operations Revision Notes (SL/HL) | RevisionDojo

File-Processing Operations

Opening a File

Files must be opened before use.
Modes:
1. Read (r) → Reads data from a file (must exist).
2. Write (w) → Creates or overwrites a file.
3. Append (a) → Adds data to the end of a file.

Example

Python:

open("data.txt", "r")

Java:

Scanner sc = new Scanner(new File("data.txt"))

Common Mistake

Using "w" when you mean "a" → existing data is lost.

Reading from a File

Methods to read:

Entire file (read() in Python).

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Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris.
Duis aute irure dolor in reprehenderit in voluptate velit esse cillum.

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File-Processing Operations

Opening a File

Files must be opened before use.
Modes:
1. Read (r) → Reads data from a file (must exist).
2. Write (w) → Creates or overwrites a file.
3. Append (a) → Adds data to the end of a file.

Example

Python:

open("data.txt", "r")

Java:

Scanner sc = new Scanner(new File("data.txt"))

Common Mistake

Using "w" when you mean "a" → existing data is lost.

Reading from a File

Methods to read:

Entire file (read() in Python).

Definition

Paywall

(on a website) an arrangement whereby access is restricted to users who have paid to subscribe to the site.

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Note

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam quis nostrud exercitation.

Excepteur sint occaecat cupidatat non proident

Tip

Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris.
Duis aute irure dolor in reprehenderit in voluptate velit esse cillum.

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A1 Computer fundamentals4 subtopics

A2 Networks4 subtopics

A3 Databases4 subtopics

A4 Machine learning4 subtopics

B1 Computational thinking1 subtopic

B2 Programming5 subtopics

B3 Object-oriented programming2 subtopics

B4 Abstract data types (HL only)1 subtopic

IB Computer Science Topic B2.5.1: Constructing Code to Perform File-processing Operations Notes

A1 Computer fundamentals4 subtopics

A2 Networks4 subtopics

A3 Databases4 subtopics

A4 Machine learning4 subtopics

B1 Computational thinking1 subtopic

B2 Programming5 subtopics

B3 Object-oriented programming2 subtopics

B4 Abstract data types (HL only)1 subtopic

File-Processing Operations

Opening a File

Reading from a File

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Excepteur sint occaecat cupidatat non proident

Unlock the rest of this chapter with a free account

File-Processing Operations

Opening a File

Reading from a File

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Excepteur sint occaecat cupidatat non proident

Unlock the rest of this chapter with a free account