从文本文件中删除空行、点和逗号

Question

I want to remove empty lines, dots and commas from my textfile. I am not really sure how to do it. I tried different metods but didnt get any results

filename = "phil.txt"
def countLines():
    """
    Read number of lines in the text file.
    """
    numOflines = 0


    with open(filename) as file:

        for line in file:
            numOflines += 1
    print("Total number of lines is: ", numOflines)
    return numOflines
countLines()

I get 19 lines but the answer should be 17 lines. I addition I want to also remove commas and dots for later use.

Answer 1

Please check the following solution and follow comments in code:

def clean(lines):
    """remove empty lines, commas and dots """
    new_lines = []  # create output list for new file
    for line in lines:
        if line != "\n":  # if not empty line let's check for . and ,
            new_line = ""  # basis for new line
            for letter in line: # check letter in line
                if letter == "." or letter == ",":
                    new_line += ""  # if you want space just use " " instead of ""
                else:
                    new_line += letter # otherwise just add old letter
            new_lines.append(new_line)
    return new_lines


if __name__ == "__main__":

    lines = []  # read lines from file
    with open("testfile.txt", mode="r") as f:  # read all lines from file
        for i in f:
            lines.append(i)

    with open("testfile.txt", mode="w") as f:  # open file again to rewrite 
        for line in clean(lines):  # clean lines of all file 
            f.write(line)  # write new lines to file 

I hope that you problem is solved, feel free to ask questions.

Answer 2

I'd do something like:

replaced_characters = {'\r\n': '\n', '\n\n': '\n', ',': ' ', '.':' ', '  ': ' '}

with open('file.ext', 'r') as f:
    text = f.read()

for k, v in replaced_characters.items():
    text = text.replace(k, v)

print(text)

I haven't tested it.