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Getting the first character of a string with $str[0]
...am just not sure whether this is 'good practice', as that notation is generally used with arrays. This feature doesn't seem to be very well documented so I'm turning to you guys to tell me if it's all right – in all respects – to use this notation?
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Is Big O(logn) log base e?
...nary 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 impli...
How do you echo a 4-digit Unicode character in Bash?
...d like to add the Unicode skull and crossbones to my shell prompt (specifically the 'SKULL AND CROSSBONES' (U+2620)), but I can't figure out the magic incantation to make echo spit it, or any other, 4-digit Unicode character. Two-digit one's are easy. For example, echo -e "\x55", .
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JavaScript for detecting browser language preference [duplicate]
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I think the main problem here is that the browser settings don't actually affect the navigator.language property that is obtained via javascript.
What they do affect is the HTTP 'Accept-Language' header, but it appears this value is not available through javascript at all. (Probably why @and...
Importing from a relative path in Python
...his method is still commonly used in some situations, where you aren't actually ever 'installing' your package. For example, it's popular with Django users.
You can add Common/ to your sys.path (the list of paths python looks at to import things):
import sys, os
sys.path.append(os.path.join(os.p...
What's the difference between the atomic and nonatomic attributes?
...o are identical; "atomic" is the default behavior (note that it is not actually a keyword; it is specified only by the absence of nonatomic -- atomic was added as a keyword in recent versions of llvm/clang).
Assuming that you are @synthesizing the method implementations, atomic vs. non-atomic chang...
Android ACTION_IMAGE_CAPTURE Intent
...works just fine if we leave out the EXTRA_OUTPUT extra and returns the small Bitmap image. However, if we putExtra(EXTRA_OUTPUT,...) on the intent before starting it, everything works until you try to hit the "Ok" button in the camera app. The "Ok" button just does nothing. The camera app stays ...
Best way to test if a row exists in a MySQL table
...RE ...)
and per the documentation, you can SELECT anything.
Traditionally, an EXISTS subquery starts with SELECT *, but it could
begin with SELECT 5 or SELECT column1 or anything at all. MySQL
ignores the SELECT list in such a subquery, so it makes no difference.
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Determine function name from within that function (without using traceback)
... Combining @CamHart's approach with @Yuval's avoids "hidden" and potentially deprecated methods in @RoshOxymoron's answer as well as numerical indexing into the stack for @neuro/@AndreasJung's answer: print(inspect.currentframe().f_code.co_name)
– hobs
Mar 1...
Checking a Python module version at runtime
...s have an attribute which holds the version information for the module (usually something like module.VERSION or module.__version__ ), however some do not.
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