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Why can I not push_back a unique_ptr into a vector?
...to a local variable. The lifetime of a local variable is managed automatically: local variables are destroyed when the block ends (e.g., when the function returns, in this case). You need to dynamically allocate the object:
std::unique_ptr<int> ptr(new int(1));
...
Only read selected columns
...g","Sep","Oct","Nov","Dec"))
dat <- fread("data.txt", drop = c(8:13))
All result in:
> data
Year Jan Feb Mar Apr May Jun
1 2009 -41 -27 -25 -31 -31 -39
2 2010 -41 -27 -25 -31 -31 -39
3 2011 -21 -27 -2 -6 -10 -32
UPDATE: When you don't want fread to return a data.table, use the data.ta...
Checking if an instance's class implements an interface?
...
As therefromhere points out, you can use class_implements(). Just as with Reflection, this allows you to specify the class name as a string and doesn't require an instance of the class:
interface IInterface
{
}
class TheClass implements IInterface
{
}
$interfaces = cl...
How do I initialize the base (super) class?
... and invoke their base class through super(), e.g.
class X(object):
def __init__(self, x):
pass
def doit(self, bar):
pass
class Y(X):
def __init__(self):
super(Y, self).__init__(123)
def doit(self, foo):
return super(Y, self).doit(foo)
Because python knows about old- an...
Implementing slicing in __getitem__
...
The __getitem__() method will receive a slice object when the object is sliced. Simply look at the start, stop, and step members of the slice object in order to get the components for the slice.
>>> class C(object):
......
Rename specific column(s) in pandas
I've got a dataframe called data . How would I rename the only one column header? For example gdp to log(gdp) ?
5 Answe...
How do I override __getattr__ in Python without breaking the default behavior?
I want to override the __getattr__ method on a class to do something fancy but I don't want to break the default behavior.
...
Getting an empty JQuery object
...tion about it, but I solved it by using PHP instead of jQuery so I can't really dig more into it right now.
– cregox
Mar 2 '11 at 19:02
2
...
How does BLAS get such extreme performance?
...e optimization. This boost significantly exceeds the second boost from parallelism and other hardware optimizations.
By the way, most (or even all) of the high performance BLAS implementations are NOT implemented in Fortran. ATLAS is implemented in C. GotoBLAS/OpenBLAS is implemented in C and i...
How to use a custom comparison function in Python 3?
...e a workaround, but I think I am going to lose some performance by passing all the comparison operators < > = to middle man, since my original custom sort is written in C , it had around 1/2x speed of default sort.
– YOU
Mar 28 '10 at 5:26
...