Reading and writing text files, splitting a line into the fields of a record, totalling, filtering and updating records, reading until a rogue value, and completing and refining a program.
What you will learn
- Split a record into fields and convert number fields
- Total, filter and pick the best record from a file
- Update one record and keep the rest
- Complete and refine a program one feature at a time
Files and records
A text file stores lines of text.
A record is one line that holds several fields, often separated by commas: Aisha,15,Leeds holds a name, an age and a town.
# Reading a file in Python
file = open("members.txt", "r")
for line in file:
line = line.strip()
print(line)
file.close()
# Writing to a file
file = open("scores.txt", "w")
file.write("Aisha,42\n")
file.close()OCR style uses openRead, readLine(), endOfFile() and close(); AQA papers describe the file in words. In the questions here the lines have already been read into a list of strings, one string per line, so you can concentrate on what to do with them.
The rest of this lesson and its 9 practice questions are locked.
In this lesson
- Files and records
- Splitting a record
- Reading until a rogue value
- Complete and refine a program
- Try it: One field from a record
9 practice questions, marked as you go; about 35 minutes in all.
Key terms
Record, Fields
In this unit: Writing code
Write real Python that runs against tests: functions, validation and logins, strings, lists and 2D lists, records, and completing and refining a program.