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Are tuples more efficient than lists in Python?
...l be more like the tuple example above than the list example, but do you really believe that means performance will be similar?
– mzz
Jan 31 '10 at 15:21
...
What does the exclamation mark mean in a Haskell declaration?
...
It's a strictness declaration. Basically, it means that it must be evaluated to what's called "weak head normal form" when the data structure value is created. Let's look at an example, so that we can see just what this means:
data Foo = Foo Int Int !Int !(May...
What characters are allowed in DOM IDs? [duplicate]
...
Actually there is a difference between HTML and XHTML.
As XHTML is XML the rules for XML IDs apply:
Values of type ID MUST match the Name production.
NameStartChar ::= ":" | [A-Z] | "_" | [a-z] | [#xC0-#xD6] |
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How to find what code is run by a button or element in Chrome using Developer Tools
...ess the F11 key (Step In) until desired source code appears
Source code finally reached
In the jsFiddle sample provided above, I had to press F11 108 times before reaching the desired event handler/function
Your mileage may vary, depending on the version of jQuery (or framework library) used to bi...
Is there an exponent operator in C#?
...o in most programs, and
it doesn't seem justified to add an
operator when calling Math.Pow() is
simple.
You asked:
Do I have to write a loop or include
another namespace to handle
exponential operations? If so, how do
I handle exponential operations using
non-integers?
Math.Pow supports double p...
Double vs. BigDecimal?
...tudes (say d1=1000.0 and d2=0.001) could result in the 0.001 being dropped alltogether when summing as the difference in magnitude is so large. With BigDecimal this would not happen.
The disadvantage of BigDecimal is that it's slower, and it's a bit more difficult to program algorithms that way (du...
Which is more efficient, a for-each loop, or an iterator?
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If you are just wandering over the collection to read all of the values, then there is no difference between using an iterator or the new for loop syntax, as the new syntax just uses the iterator underwater.
If however, you mean by loop the old "c-style" loop:
for(int i=0; i&l...
How to make the 'cut' command treat same sequental delimiters as one?
... characters to tab. For example: I came here looking for a way to automatically export my display: who am i | tr -s ' ()' '\t' | cut -f5
– Leo
Mar 28 '16 at 23:24
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How to Select Every Row Where Column Value is NOT Distinct
I need to run a select statement that returns all rows where the value of a column is not distinct (e.g. EmailAddress).
7 A...
Iterating C++ vector from the end to the beginning
...;
i != my_vector.rend(); ++i ) {
}
rbegin()/rend() were especially designed for that purpose. (And yes, incrementing a reverse_interator moves it backward.)
Now, in theory, your method (using begin()/end() & --i) would work, std::vector's iterator being bidirectional, but remember,...