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What's quicker and better to determine if an array key exists in PHP?
... if the value is NULL.
Whereas
isset() will return false if the key exist and value is NULL.
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In a Git repository, how to properly rename a directory?
... to copy the directory to be renamed to a new directory with desired name, and delete the old directory , and git add , git commit and push everything. But is this the best way?
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CRON job to run on the last day of the month
...ed to find another way.
However, it's usually both substantially easier and correct to run the job as soon as possible on the first day of each month, with something like:
0 0 1 * * myjob.sh
and modify the script to process the previous month's data.
This removes any hassles you may encounter...
CSS scrollbar style cross browser [duplicate]
...CSS scrollbar style cross browser? I tested this code, it only works in IE and opera, but failed in Chrome, Safari and Firefox.
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What is the difference between __init__ and __call__?
I want to know the difference between __init__ and __call__ methods.
13 Answers
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Why is setTimeout(fn, 0) sometimes useful?
...o initialize the drop-down list, ready to have its selected index updated, and
Your code to set the selected index
Your code was consistently winning this race and attempting to set drop-down selection before the browser was ready, meaning that the bug would appear.
This race existed because Java...
How to update a plot in matplotlib?
...ure here. I allow the user to specify the units in the time scale (x-axis) and then I recalculate and call this function plots() . I want the plot to simply update, not append another plot to the figure.
...
What does auto do in margin:0 auto?
... parameter basically tells the browser to automatically determine the left and right margins itself, which it does by setting them equally. It guarantees that the left and right margins will be set to the same size. The first parameter 0 indicates that the top and bottom margins will both be set to ...
When is CRC more appropriate to use than MD5/SHA1?
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CRC works fine for detecting random errors in data that might occur, for example, from network interference, line noise, distortion, etc.
CRC is computationally much less complex than MD5 or SHA1. Using a hash function like MD5 is probably overkill for r...
Resumable downloads when using PHP to send the file?
...tent. Then, if request with a Range: bytes=x-y header is received (with x and y being numbers) you parse the range the client is requesting, open the file as usual, seek x bytes ahead and send the next y - x bytes. Also set the response to HTTP/1.0 206 Partial Content.
Without having tested anythi...