Lining Up and PaddingTwo Similar Lists

[W. eWatson]

castironpi wrote:
...

> 
> I don't think that's guaranteed by anything.  I realized that
> 'dat.sort()' and 'txt.sort()' weren't necessary, since their contents
> are moved to a dictionary, which isn't sorted.
Actually, I'm getting the file names from listdir, and they appear to be 
sorted low to high. I tried it on a folder with lots of dissimilar files.
> 
> both= set( datD.keys() )& set( txtD.keys() )
> 
> This will get you the keys (prefixes) that are in both.  Then for
> every prefix if it's not in 'both', you can report it.
> 
> Lastly, since you suggest you're guaranteed that 'txt' will all share
> the same extension, you can do away with the dictionary and use sets
> entirely.  Only if you can depend on that assumption.
Each dat file contains an image, and its description and related parameters 
are in the corresponding txt file.
> 
> I took a look at this.  It's probably more what you had in mind, and
> the dictionaries are overkill.
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