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Python: List vs Dict for look up table
... amortized O(1), with regard to the number of items in the data structure. If you don't need to associate values, use sets.
Memory
Both dictionaries and sets use hashing and they use much more memory than only for object storage. According to A.M. Kuchling in Beautiful Code, the implementation tri...
How to set HTTP headers (for cache-control)?
...o be HTTP/1.1 compliant. Also see EXPIRES.
Note: It may be better to specify cache commands in HTTP than in META statements, where they can influence more than the browser, but proxies and other intermediaries that may cache information.
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Get yesterday's date in bash on Linux, DST-safe
...that switching between summer and winter time is always done during night, if I understand correctly?
– Nicolas Raoul
Mar 28 '17 at 3:38
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How to put an image in div with CSS?
...nt/
This has been tested on Chrome, firefox and Safari. (I'm on a mac, so if someone has the result on IE, tell me to add it)
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How to delete a certain row from mysql table with same column values?
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This only deletes one row. If there were 3 with this user and product id then 2 would remain.
– Rob
Aug 22 '13 at 10:48
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Better way to revert to a previous SVN revision of a file?
...thing - say, I'm at revision 855, I want to revert a file to revision 854. If I do svn merge -c -854 my.file, and then do svn diff, it seems to show one revision before 854 (that is, 853); only when I do svm merge -c 854 myfile (without the -), it looks like myfile is reverted to rev 854. Thanks aga...
Read and overwrite a file in Python
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If you don't want to close and reopen the file, to avoid race conditions, you could truncate it:
f = open(filename, 'r+')
text = f.read()
text = re.sub('foobar', 'bar', text)
f.seek(0)
f.write(text)
f.truncate()
f.close()
Th...
What is the X-REQUEST-ID http header?
...en you're operating a webservice that is accessed by clients, it might be difficult to correlate requests (that a client can see) with server logs (that the server can see).
The idea of the X-Request-ID is that a client can create some random ID and pass it to the server. The server then include th...
Convert Pixels to Points
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There are 72 points per inch; if it is sufficient to assume 96 pixels per inch, the formula is rather simple:
points = pixels * 72 / 96
There is a way to get the configured pixels per inch of your display in Windows using GetDeviceCaps. Microsoft has a...
Using Application context everywhere?
...ith anything that deals with the GUI that requires a Context. For example, if you pass the application Context into the LayoutInflater you will get an Exception. Generally speaking, your approach is excellent: it's good practice to use an Activity's Context within that Activity, and the Application ...