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Transpose/Unzip Function (inverse of zip)?
...! Provided you use the special * operator.
>>> zip(*[('a', 1), ('b', 2), ('c', 3), ('d', 4)])
[('a', 'b', 'c', 'd'), (1, 2, 3, 4)]
The way this works is by calling zip with the arguments:
zip(('a', 1), ('b', 2), ('c', 3), ('d', 4))
… except the arguments are passed to zip directly (...
Remove duplicate dict in list in Python
...where the tuples contain the items of the dictionary. Since the tuples can be hashed, you can remove duplicates using set (using a set comprehension here, older python alternative would be set(tuple(d.items()) for d in l)) and, after that, re-create the dictionaries from tuples with dict.
where:
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How to 'minify' Javascript code
JQuery has two versions for download, one is Production (19KB, Minified and Gzipped) , and the other is Development (120KB, Uncompressed Code) .
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Is short-circuiting logical operators mandated? And evaluation order?
Does the ANSI standard mandate the logical operators to be short-circuited, in either C or C++?
7 Answers
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What is the exact problem with multiple inheritance?
I can see people asking all the time whether multiple inheritance should be included into the next version of C# or Java. C++ folks, who are fortunate enough to have this ability, say that this is like giving someone a rope to eventually hang themselves.
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The Definitive C++ Book Guide and List
This question attempts to collect the few pearls among the dozens of bad C++ books that are published every year.
1 Answer
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ggplot2 keep unused levels barplot
I want to plot unused levels (that is, levels where the count is 0) in my bar-plot, however, unused levels are dropped and I cannot figure out how to keep them
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Python add item to the tuple
I have some object.ID-s which I try to store in the user session as tuple. When I add first one it works but tuple looks like (u'2',) but when I try to add new one using mytuple = mytuple + new.id got error can only concatenate tuple (not "unicode") to tuple .
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How to get row from R data.frame
...- structure(list(A = c(5, 3.5, 3.25, 4.25, 1.5 ),
B = c(4.25, 4, 4, 4.5, 4.5 ),
C = c(4.5, 2.5, 4, 2.25, 3 )
),
.Names = c("A", "B", "C"),
class = "data.frame",
row.names = c...
dynamic_cast and static_cast in C++
...types are not related, you will get a compiler error. For example:
class B {};
class D : public B {};
class X {};
int main()
{
D* d = new D;
B* b = static_cast<B*>(d); // this works
X* x = static_cast<X*>(d); // ERROR - Won't compile
return 0;
}
dynamic_cast< Type* >(p...