Re: compare dictionary values

Marc 'BlackJack' Rintsch wrote: 
In <dp4124$pki$1@xxxxxxxxxxxxxxxxx>, rbt wrote:

What's a good way to compare values in dictionaries? 

Look them up and then compare!?  ;-)

I want to find values that have changed. I look for new keys by doing this:

new = [k for k in file_info_cur.iterkeys() if k not in file_info_old.iterkeys()]
if new == []:
print new, "No new files."
else:
print new, "New file(s)!!!"

My key-values pairs are filepaths and their modify times. I want to identify files that have been updated or added since the script last ran. 

This looks up each `key` from the `new` dictionary and compares the value
with the `old` one.  If it's not equal or the key is not present in `old`
the key is appended to the `result`::

 def new_and_changed_keys(old, new):
     result = list()
     for (key, value) in new:
         try:
             if old[key] != value:
                 result.append(key)
         except KeyError:
             result.append(key)
     return result

Ciao,
	Marc 'BlackJack' Rintsch


Thanks Marc! I changed this line:

for (key, value) in new:

To this:

for (key, value) in new.iteritems():

And, it works great. Thanks again.
.

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