2.3.4 Methods of File Access

Words.txt is a list of words that are allowable in crossword puzzles.

NB Each line only has a single word on it.

You will need to import the file using the IMPORT function followed by the file name.

You will also need to open the file in read only mode to access the data.

OPEN is a Built-In FUNCTION that takes the <file name> as a parameter

and RETURNS a file object you can use to read the filer.

fin = OPEN('words.txt') #Fin is a commonly used name for file objects used for input.

PRINT fin #RESERVED words in capitals need to be lower case in Python

open file 'words.txt', mode 'r' # mode 'r' indicates the file is open for read only

READLINE is a method for reading characters from the file until it gets to a new line

and RETURNS the result a STRING

fin.readline()

Task 1

Write a program that reads each line of words.txt and prints any words with more than 20 characters.

save as <filename>_v1

Task 2

Modify your program to return all the words begining with 'q'

save as <filename>_v2

Task 3

Now, Modify your program to return all the words ending with 'ually'

save as <filename>_v3

Task 4

Modify your program to return onlt the words without an 'e'

save as <filename>_v4

Task 5

Write a function called avoids that takes a word and a string of forbidden letters

and RETURNS TRUE if the word uses none of the forbidden letters.

Extension: Find a combination of 5 letters that excludes the smallest number of words

Task 6

Write a function called anagram, that takes a word and a string of letters

and RETURNS TRUE if the word uses only those letters. (ie an anagram)

Task 7

Modify the function and save as uses_only, so that it takes a word and a string of letters

and RETURNS TRUE if the word uses all of the letters at least once.

Extension

Write a function called abecedarian that returns TRUE if the letters of a word appear in alphabetical order. (Double letters OK)

How many abecedaian words are there?