Question

Write a function named mostFrequent that takes two parameters: 1. inFile, a string that is the name of an input file 2. outFile, a string that is the name of an output file The input file inFile exists when mostFrequent is called; mostFrequent must create outFile. The input file contains only lower case letters and white space. The function mostFrequent identifies the letter(s) that appear most frequently on each line of inFile and writes them to a corresponding line of outFile. If more than one letter on a line has the same frequency, they should each be written to outFile. Each letter should be written to a line only once. For example, if the file moreYouKnow.txt contains the following lines: the more that you read the more things you will know then the function call mostFrequent('moreYouRead.txt', 'moreYouReadOut.txt') should produce an output file moreYouReadOut.txt with the following lines: te o Hint: the space character " " is not a letter and so can not be a most frequent letter.

Python language

Answer 1

def mostFrequent(inputFilename, outputFilename):
    try:
        f = open(inputFilename, 'r')
        w = open(outputFilename, 'w')
        for line in f:
            line = line.strip()
            chars = []
            largestCount = 0
            for ch in line:
                if ch != ' ' and line.count(ch) > largestCount:
                    largestCount = line.count(ch)
            for ch in line:
                if ch not in chars and line.count(ch) == largestCount:
                    chars.append(ch)
                    w.write(ch)
            w.write('\n')
        f.close()
        w.close()
    except FileNotFoundError:
        print(inputFilename + " does not exists!")


mostFrequent('moreYouRead.txt', 'moreYouReadOut.txt')