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Why is string concatenation faster than array join?
...ring concatenation. Beginning with version 1.0, the array technique is actually slower than using the plus operator in all cases. Other browsers have also optimized string concatenation, so Safari, Opera, Chrome, and Internet Explorer 8 also show better performance using the plus operator. Internet ...
What is __init__.py for?
...kages as they existed in Python 3.2 and earlier. A regular package is typically implemented as a directory containing an __init__.py file. When a regular package is imported, this __init__.py file is implicitly executed, and the objects it defines are bound to names in the package’s namespace. The...
Number of processors/cores in command line
...
Make sure to nproc --all for all installed Processing Units. Without --all, nproc only shows Processing Units available to the current process. Read the man page for more details. MMV.
– JamesThomasMoon1979
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Are PHP functions case sensitive?
I was digging through some code, and I found some calls to mySQL_fetch_array . Is PHP case sensitive about function names? I recall reading this somewhere but can't seem to find any reference to it.
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append multiple values for one key in a dictionary [duplicate]
...st of values associated with that year, right? Here's how I'd do it:
years_dict = dict()
for line in list:
if line[0] in years_dict:
# append the new number to the existing array at this slot
years_dict[line[0]].append(line[1])
else:
# create a new array in this slo...
What's wrong with overridable method calls in constructors?
...ohibit it:
There are a few more restrictions that a class must obey to allow inheritance. Constructors must not invoke overridable methods, directly or indirectly. If you violate this rule, program failure will result. The superclass constructor runs before the subclass constructor, so the overr...
Where is Java Installed on Mac OS X?
...ownloaded Java 7u17 on Mac OS 10.7.5 from here and then successfully installed it. In order to do some JNI programming, I need to know where Java installed on my Mac.
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Is there a way to 'uniq' by column?
...o you need the ,1 in -k1,1? why not just -k1?
– hello_there_andy
Nov 24 '14 at 20:10
19
@hello_th...
When should you use constexpr capability in C++11?
... "function that always returns 5" is breaking or diluting the meaning of "calling a function". There must be a reason, or a need for this capability or it wouldn't be in C++11. Why is it there?
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How do I find out what keystore my JVM is using?
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Your keystore will be in your JAVA_HOME---> JRE -->lib---> security--> cacerts. You need to check where your JAVA_HOME is configured, possibly one of these places,
Computer--->Advanced --> Environment variables---> JAVA_HOME
Your serv...