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What is more efficient: Dictionary TryGetValue or ContainsKey+Item?
...property actually has nearly identical code functionality as TryGetValue, em>x m>cept that it will throw an em>x m>ception instead of returning false.
Using ContainsKey followed by the Item basically duplicates the lookup functionality, which is the bulk of the computation in this case.
...
Why is enum class preferred over plain enum?
...++ has two kinds of enum:
enum classes
Plain enums
Here are a couple of em>x m>amples on how to declare them:
enum class Color { red, green, blue }; // enum class
enum Animal { dog, cat, bird, human }; // plain enum
What is the difference between the two?
enum classes - enumerator names are local ...
Python CSV error: line contains NULL byte
...reported by reader.line_num will be (unhelpfully) 1. Find where the first \m>x m>00 is (if any) by doing
data = open('my.csv', 'rb').read()
print data.find('\m>x m>00')
and make sure that you dump at least that many bytes with repr or od.
What does data.count('\m>x m>00') tell you? If there are many, you may w...
Efficiently convert rows to columns in sql server
...tNumber
from
(
select value, columnname
from yourtable
) d
pivot
(
mam>x m>(value)
for columnname in (Firstname, Amount, PostalCode, LastName, AccountNumber)
) piv;
See Demo.
Pivot with unknown number of columnnames
If you have an unknown number of columnnames that you want to transpose, then...
What is the result of % in Python?
...rted to a common type. A zero right argument raises the ZeroDivisionError em>x m>ception. The arguments may be floating point numbers, e.g., 3.14%0.7 equals 0.34 (since 3.14 equals 4*0.7 + 0.34.) The modulo operator always yields a result with the same sign as its second operand (or zero); the absolute v...
What is the worst real-world macros/pre-processor abuse you've ever come across?
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1
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Nem>x m>t
410
votes
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How can I profile C++ code running on Linum>x m>?
I have a C++ application, running on Linum>x m>, which I'm in the process of optimizing. How can I pinpoint which areas of my code are running slowly?
...
Getting All Variables In Scope
...rt("arguments[" + n + "][" + name + "]=" + arg[name]);
}
}
(You can em>x m>pand on that to get more useful information.)
Instead of that, though, I'd probably use a debugger like Chrome's dev tools (even if you don't normally use Chrome for development) or Firebug (even if you don't normally use F...
No module named pkg_resources
... server and am hitting this error when I run pip install -r requirements.tm>x m>t :
34 Answers
...
`from … import` vs `import .` [duplicate]
... @g.d.d.c: The “single trailing underscore” convention is em>x m>plicitly specified by PEP 8 (twice). If Eclipse produces annoying warnings about correct code, then we have a bad IDE, not a bad habit.
– wchargin
Feb 16 '18 at 9:11
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