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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...
How does libuv compare to Boost/ASIO?
...s. For this reason, care needs to be taken when using the default loop (uv_default_loop()), rather than creating a new loop (uv_loop_new()), as another component may be running the default loop.
Boost.Asio does not have the notion of a default loop; all io_service are their own loops that allow for...
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...
Received an invalid column length from the bcp client for colid 6
...act 1 from it to get the value. After that it is used as the index of the _sortedColumnMappings ArrayList of the SqlBulkCopy instance not the index of the column mappings that were added to the SqlBulkCopy instance. One thing to note is that SqlBulkCopy will stop on the first error received so thi...
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...
Detecting iOS / Android Operating system
...ng iPAD Pro: return this: Safari: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.0 Safari/605.1.15
– Ivan Ferrer
Jun 9 at 18:24
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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?
6 ...
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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