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Why dict.get(key) instead of dict[key]?
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It allows you to provide a default value if the key is missing:
dictionary.get("bogus", default_value)
returns default_value (whatever you choose it to be), whereas
dictionary["bogus"]
would raise a KeyError.
If omitted...
Undocumented NSURLErrorDomain error codes (-1001, -1003 and -1004) using StoreKit
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All error codes are on "CFNetwork Errors Codes References" on the documentation (link)
A small extraction for CFURL and CFURLConnection Errors:
kCFURLErrorUnknown = -998,
kCFURLErrorCancelled = -999,
kCFURLErrorBadU...
Hidden Features of PHP? [closed]
...and getting a reference most of the time is great.
– Allain Lalonde
Sep 14 '08 at 17:46
1
This is...
Run certain code every n seconds [duplicate]
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This seems not to resolve the question at all... it does not repeat every second.
– Yan King Yin
Jul 5 '13 at 15:28
9
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JRE 1.7 - java version - returns: java/lang/NoClassDefFoundError: java/lang/Object
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This problem stems from an improper Java installation.
Possibility 1
NOTE: This scenario only applies to Java 8 and prior. Beginning with Java 9, the JRE is structured differently. rt.jar and friends no longer exist, and Pack200 is no longer used.
The Java standa...
Multiple Models in a single django ModelForm?
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But how? Usually a FormView only has a single form_class assigned to it.
– erikbwork
Oct 7 '16 at 17:42
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Approximate cost to access various caches and main memory?
...xample, check page 22 for some timings & cycles for example).
Additionally, this page has some details on clock cycles etc. The second link served the following numbers:
Core i7 Xeon 5500 Series Data Source Latency (approximate) [Pg. 22]
local L1 CACHE hit, ...
What's the $unwind operator in MongoDB?
...hat it stores your data is in the form of documents and collections, which allows for a dynamic means of adding and obtaining the data from your storage locations.
That being said, in order to understand the concept behind the $unwind parameter, you first must understand what the use case that you ...
Algorithm to detect corners of paper sheet in photo
...n are awesome, move to them as soon as possible. :D
Instead of removing small objects and or noise, lower the canny restraints, so it accepts more edges, and then find the largest closed contour (in OpenCV use findcontour() with some simple parameters, I think I used CV_RETR_LIST). might still stru...
What is the command to list the available avdnames
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List all your emulators: emulator -list-avds Run one of the listed emulators: emulator @name-of-your-emulator where emulator is under: ${ANDROID_SDK}/tools/emulator
– Dhiraj Himani
Jun 16 ...