Graphically view the difference of a long string that basically matches

Question

I have two data files. They are 5,000 lines long, and each line is ~ 10,000 characters wide. They are almost identical, with the exception of a few characters on some lines. Is there any tool that will jump both vertically and horizontally to the odds for both sides, so I can see what is different?

I use OSX, but I could use Linux or Windows if it was absolutely necessary. I tried:

• Filemerge
• Kiff3
• Diffmerge
• command line diff
• Now, trying to install meld

Answer 1

vimdiff, or even better its graphical double gvimdiff, will work if there are no more than two changes in a line. It highlights the part between the first and last changed characters on the line. It also destroys parts of files that are identical.

This is part of Vim ; I have no idea if macOS (g) vimdiff versions exist.

Please note that in my experience, Vim sometimes gets slow with long strings, so this may hurt you in this particular use case.

Answer 2

Araxis Merge can do what you need (these are characteristic line differences), as well as the OSX version. It's not cheap, and I have never tried it on lines with a width of 10,000 characters.