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Difference between malloc and calloc?
..., while malloc() leaves the memory uninitialized.
For large allocations, most calloc implementations under mainstream OSes will get known-zeroed pages from the OS (e.g. via POSIX mmap(MAP_ANONYMOUS) or Windows VirtualAlloc) so it doesn't need to write them in user-space. This is how normal malloc ...
Matplotlib - Move X-Axis label downwards, but not X-Axis Ticks
...red Jul 29 '14 at 14:57
Matthias123Matthias123
79266 silver badges1313 bronze badges
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How to convert index of a pandas dataframe into a column?
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df1 = pd.DataFrame({"gi":[232,66,34,43],"ptt":[342,56,662,123]})
p = df1.index.values
df1.insert( 0, column="new",value = p)
df1
new gi ptt
0 0 232 342
1 1 66 56
2 2 34 662
3 3 43 123
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In Python script, how do I set PYTHONPATH?
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It has been many years since this answer was posted, but I still want to add that if you want to make sure that Python checks the new directory before all of the others when importing, you should put the new directory first in the list, as in sys.path.insert(0, '/path/to...
Negation in Python
...herefore just replace your ! with not.
For your example, do this:
if not os.path.exists("/usr/share/sounds/blues") :
proc = subprocess.Popen(["mkdir", "/usr/share/sounds/blues"])
proc.wait()
For your specific example (as Neil said in the comments), you don't have to use the subprocess ...
How can I remove a character from a string using Javascript?
...et of charcters> could be characters described by a character class:
/[123!y]/
//any one of these
/[^123!y]/
//anything but one of the chars following '^' (very useful/performance enhancing btw)
Or expanded on to match a quantity of characters (but still best to think of as a single element in...
How can I programmatically determine if my app is running in the iphone simulator?
...r "Compiling source code conditionally"
The relevant definition is TARGET_OS_SIMULATOR, which is defined in /usr/include/TargetConditionals.h within the iOS framework. On earlier versions of the toolchain, you had to write:
#include "TargetConditionals.h"
but this is no longer necessary on the c...
What exactly is Python's file.flush() doing?
...t has been "permanently" stored on disk.
To do that, you need to call the os.fsync method which ensures all operating system buffers are synchronized with the storage devices they're for, in other words, that method will copy data from the operating system buffers to the disk.
Typically you don't ...
How do I run IDEA IntelliJ on Mac OS X with JDK 7?
I use Mac OS X 10.8.2, and use JDK 7. Now I downloaded the latest version of IDEA IntelliJ, 11. But it doesn't seem to start without JDK 6. Is there any workaround?
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How to read a file in reverse order?
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Also, while the posted code does answer the question, we should be careful to close files that we open. The with statement is usually quite painless.
– William
Mar 7 '13 at 14:41
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