Loop through .txt to create two delimiters depending on data index-CodePudding

So I have a number of files (1000ish) each with 90k plus lines, where the data was recorded in the incorrect format and I am trying to make reformat the txt files.

The data currently looks like this:

9/3/2021 00 00 00 -0.18 -2.40 -2.40
9/3/2021 00 00 01 -0.18 -2.40 -2.40
9/3/2021 00 00 02 -0.18 -2.40 -2.40
9/3/2021 00 00 03 -0.17 -2.40 -2.40
.....

However, it should look like

9/3/2021,00:00:00,-0.18, , ,-2.40,-2.40
9/3/2021,00:00:01,-0.18, , ,-2.40,-2.40
9/3/2021,00:00:02,-0.18, , ,-2.40,-2.40
9/3/2021,00:00:03,-0.17, , ,-2.40,-2.40
....

I have managed to go through everything and add a " , " with

input = open(os.path.expanduser("~/Desktop/ssdat/SegY TidalCorrection 03092021.txt"))
content = input.read()
content = content.replace(" ", ",")
print(content)

resulting in an output of:
9/3/2021,17,22,47,0.20,1511.10,-2.12,-2.29
9/3/2021,17,22,48,0.01,1511.10,-2.29,-2.29
9/3/2021,17,22,49,-0.17,1511.05,-2.41,-2.29
9/3/2021,17,22,50,-0.14,1511.02,-2.34,-2.30

So I guess my question is how can I loop through everything to make two new delimiters?

CodePudding user response：

One option would be to iterate through the text file line by line and then character by character. Assuming you already know how your data should be formatted, you could then look for spaces and replace them with the desired delimiter.

CodePudding user response：

Similar to @bret-hogg's answer. But if you're only interested in recreating a simple string on each line then the following will work:

import os


with open("your_old_file.txt", "r") as text_file, open("your_new_file.txt", "w") as csv_file:
    for line in text_file:
        fields = line.split(" ")
        date = fields[0]
        time = fields[1]   ":"   fields[2]   ":"   fields[3]
        replacement_row = f"{date},{time},{fields[4]},,,{fields[5]},{fields[6]}"
        csv_file.write(replacement_row)