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What is the difference between mutex and critical section?
... between the two of them. On my system for 1,000,000 uncontended acquires and releases, a mutex takes over one second. A critical section takes ~50 ms for 1,000,000 acquires.
Here's the test code, I ran this and got similar results if mutex is first or second, so we aren't seeing any other effect...
Which data type for latitude and longitude?
I am newbie to PostgreSQL and PostGIS. I want to store latitude and longitude values in PostgreSQL 9.1.1 database table. I will calculate distance between two points, find nearer points by using this location values.
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What is the default location for MSBuild logs?
... location of the log file? I have searched in the folder where my solution and projects are stored, but cannot find any .log file.
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Is there an eval() function in Java? [duplicate]
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You can use the ScriptEngine class and evaluate it as a Javascript string.
ScriptEngineManager manager = new ScriptEngineManager();
ScriptEngine engine = manager.getEngineByName("js");
Object result = engine.eval("4*5");
There may be a better way, but this ...
Chaining multiple MapReduce jobs in Hadoop
...be passed in as arguments to your jobs with appropriate code to parse them and set up the parameters for the job.
I think that the above method might however be the way the now older mapred API did it, but it should still work. There will be a similar method in the new mapreduce API but i'm not sure...
What is “:-!!” in C code?
... effect, a way to check whether the expression e can be evaluated to be 0, and if not, to fail the build.
The macro is somewhat misnamed; it should be something more like BUILD_BUG_OR_ZERO, rather than ...ON_ZERO. (There have been occasional discussions about whether this is a confusing name.)
You...
Maintain the aspect ratio of a div with CSS
...rce: w3.org, emphasis mine)
Padding-bottom values for other aspect ratios and 100% width :
aspect ratio | padding-bottom value
--------------|----------------------
16:9 | 56.25%
4:3 | 75%
3:2 | 66.66%
8:5 | 62.5%
Placing content in ...
Why doesn't the height of a container element increase if it contains floated elements?
I would like to ask how height and float work. I have an outer div and an inner div that has content in it. Its height may vary depending on the content of the inner div but it seems that my inner div will overflow its outside div. What would be the proper way to do it?
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Run/install/debug Android applications over Wi-Fi?
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See forum post Any way to view Android screen remotely without root? - Post #9.
Connect the device via USB and make sure debugging is working;
adb tcpip 5555. This makes the device to start listening for connections on port 5555;
Look up the device IP ad...
What is the difference between old style and new style classes in Python?
What is the difference between old style and new style classes in Python? When should I use one or the other?
8 Answers
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