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How to convert a byte array to a hex string in Java?
I have a byte array filled with hex numbers and printing it the easy way is pretty pointless because there are many unprintable elements. What I need is the exact hexcode in the form of: 3a5f771c
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When is null or undefined used in JavaScript? [duplicate]
...nfused as to when JavaScript returns null or undefined . Also different browsers seem to be returning these differently.
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In-memory size of a Python structure
...here a reference for the memory size of Python data stucture on 32- and 64-bit platforms?
7 Answers
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Is Big O(logn) log base e?
For binary search tree type of data structures, I see the Big O notation is typically noted as O(logn). With a lowercase 'l' in log, does this imply log base e (n) as described by the natural logarithm? Sorry for the simple question but I've always had trouble distinguishing between the different...
How can I display an RTSP video stream in a web page?
...ides a live RTSP video stream. I can use VLC media player to view the feed by providing it with the URL:
15 Answers
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MySQL: Invalid use of group function
...s MySQL selects. Then MySQL groups the rows together and aggregates the numbers for your COUNT function.
HAVING is like WHERE, only it happens after the COUNT value has been computed, so it'll work as you expect. Rewrite your subquery as:
( -- where that pid is in the set:
SELECT ...
Forking from GitHub to Bitbucket
I'm working on a project based on CakePHP , that's hosted on GitHub . My project is being hosted on Bitbucket . Both of them use git . Basically I'd like to create a ‘fork’ (I don't know if I'm using the right terms, since I'm new to git ) of CakePHP in my Bitbucket repository, in order t...
Simpler way to create dictionary of separate variables?
I would like to be able to get the name of a variable as a string but I don't know if Python has that much introspection capabilities. Something like:
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PHP: How to use array_filter() to filter array keys?
The callback function in array_filter() only passes in the array's values, not the keys.
14 Answers
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How to switch to REPLACE mode in VIM
I know I can do this by pressing Insert in INSERT mode, but that requires some stretching. Is there any more convenient shortcut to go directly from NORMAL mode to REPLACE mode?
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