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reference assignment is atomic so why is Interlocked.Exchange(ref Object, Object) needed?
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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Which is faster in Python: x**.5 or math.sqrt(x)?
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In python 2.6 the (float).__pow__() function uses the C pow() function and the math.sqrt() functions uses the C sqrt() function.
In glibc compiler the implementation of pow(x,y) is quite complex and it is well optimized for various exceptional cases...
scheduleAtFixedRate vs scheduleWithFixedDelay
...run() method... Basically it's the difference between scheduling something based on when the previous execution ends and when it (logically) starts.
For example, suppose I schedule an alarm to go off with a fixed rate of once an hour, and every time it goes off, I have a cup of coffee, which takes ...
Cross-thread operation not valid: Control 'textBox1' accessed from a thread other than the thread it
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The data received in your serialPort1_DataReceived method is coming from another thread context than the UI thread, and that's the reason you see this error.
To remedy this, you will have to use a dispatcher as descibed in the MSDN article:
How to: Make Thread-S...
Switching between GCC and Clang/LLVM using CMake
...ridden by putting them into a system wide CMake file and pointing the CMAKE_USER_MAKE_RULES_OVERRIDE variable to it. Create a file ~/ClangOverrides.txt with the following contents:
SET (CMAKE_C_FLAGS_INIT "-Wall -std=c99")
SET (CMAKE_C_FLAGS_DEBUG_INIT "-g")
SET (CMAKE_C_FLA...
Programmatically selecting text in an input field on iOS devices (mobile Safari)
... FWIW, it works in Chrome Desktop and Android Browser, which are also based on WebKit.
– jrummell
Jun 22 '11 at 18:20
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How are POST and GET variables handled in Python?
In PHP you can just use $_POST for POST and $_GET for GET (Query string) variables. What's the equivalent in Python?
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In Python how should I test if a variable is None, True or False
...ry:
result = simulate(open("myfile"))
except SimulationException as sim_exc:
print "error parsing stream", sim_exc
else:
if result:
print "result pass"
else:
print "result fail"
# execution continues from here, regardless of exception or not
And now you can have a ...
pandas GroupBy columns with NaN (missing) values
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No, this is not consistent with R. df %>% group_by will give NA summaries too with a warning which can be avoided by passing the grouping column through fct_explicit_na and then a (Missing) level is created.
– Ravaging Care
Aug 16 '1...
Size of Matrix OpenCV
... Link to documentation: docs.opencv.org/modules/core/doc/basic_structures.html#mat-size
– Rasim
Dec 25 '12 at 6:50
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