Removing spaces and empty lines from a file Using Python

Question

I have a file which contains a value 2000,00.

But it contains spaces after 2000,00 and empty lines.

I want to remove all the spaces and empty lines, if some one can give some Idea, I ave tried a number of ways but no success.

One method I tired is as below

    # Read lines as a list
fh = open("transfer-out/" + file, "r")
lines = fh.readlines()
fh.close()
# Weed out blank lines with filter
lines = filter(lambda x: not x.isspace(), lines)
# Write "transfer-out/"+file+".txt", "w"
fh = open("transfer-out/"+file, "w")
#fh.write("".join(lines))
# should also work instead of joining the list:
fh.writelines(lines)
fh.close()

Answer 1

strip() removes leading and trailing whitespace characters.

with open("transfer-out/" + file, "r") as f:
    for line in f:
        cleanedLine = line.strip()
        if cleanedLine: # is not empty
            print(cleanedLine)

Then you can redirect the script into a file python clean_number.py > file.txt, for example.

Answer 2

Another one with list comprehension:

clean_lines = []
with open("transfer-out/" + file, "r") as f:
    lines = f.readlines()
    clean_lines = [l.strip() for l in lines if l.strip()]

with open("transfer-out/"+file, "w") as f:
    f.writelines('\n'.join(clean_lines))