Question

I have a few text files that I created in a separate script, but I am at a loss on how to arrange the text file in the manner that I want.

The text file has three columns:

X, Y, [Z1, Z2, Z3, …]

Where the X/Y/Z values are arbitrary numbers.

There are several lines in this file, and the Z-lists are of varying lengths. What I would like is for the Z-lists to be separated so that there is only one Z value in each line, but the X/Y values would repeat based on how many elements are in the Z list.

For example, the first two lines of the text file are:

    2306 3481 [2, -3, 82.6, 0.2]
    2336 3408 [9, 0]

I would like for the two lines to become:

    2306 3481 2
    2306 3481 -3
    2306 3481 82.6
    2306 3481 0.2
    2336 3408 9
    2336 3408 0

Answer 1

Using ast.literal_eval and str.split:

with open("abc.txt") as f:
    for line in f :
        line=line.split(None,2)  #returns ['2306', '3481', '[2, -3, 82.6, 0.2]'] 
        a,b=line[:2]   
        lis=literal_eval(line[-1])
        for x in lis:
            print a,b,x    #or write to a new file
   ....:             
2306 3481 2
2306 3481 -3
2306 3481 82.6
2306 3481 0.2
2336 3408 9
2336 3408 0