Are there any alternatives to the code below:
startFromLine = 141978 # or whatever line I need to jump to urlsfile = open(filename, "rb", 0) linesCounter = 1 for line in urlsfile: if linesCounter > startFromLine: DoSomethingWithThisLine(line) linesCounter += 1
If I'm processing a huge text file
(~15MB) with lines of unknown but different length, and need to jump to a particular line which number I know in advance? I feel bad by processing them one by one when I know I could ignore at least first half of the file. Looking for more elegant solution if there is any.
You can't jump ahead without reading in the file at least once, since you don't know where the line breaks are. You could do something like:
# Read in the file once and build a list of line offsets line_offset =  offset = 0 for line in file: line_offset.append(offset) offset += len(line) file.seek(0) # Now, to skip to line n (with the first line being line 0), just do file.seek(line_offset[n])