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How to use base class's constructors and assignment operator in C++?
...= d;}
Normally copy constructors chain so that they are copy constructed from the base up. Here because you are calling the assignment operator the copy constructor must call the default constructor to default initialize the object from the bottom up first. Then you go down again using the assignm...
Python Progress Bar
... a progress meter to your loops in a second:
In [1]: import time
In [2]: from tqdm import tqdm
In [3]: for i in tqdm(range(10)):
....: time.sleep(3)
60%|██████ | 6/10 [00:18<00:12, 0.33 it/s]
Also, there is a graphical version of tqdm since v2.0.0 (d977a0c):
In [1]:...
Start thread with member function
...ream>
class bar {
public:
void foo() {
std::cout << "hello from member function" << std::endl;
}
};
int main()
{
std::thread t(&bar::foo, bar());
t.join();
}
EDIT:
Accounting your edit, you have to do it like this:
std::thread spawn() {
return std::thread(&a...
Parse v. TryParse
... Parse throws a number of different exceptions so if all it had was a bool from TryParse then it wouldn't know which one to throw.
– Greg Beech
Jan 22 '09 at 8:42
5
...
Add column with constant value to pandas dataframe [duplicate]
...ere's how DataFrame.align() works with partially aligned indices:
In [7]: from pandas import DataFrame
In [8]: from numpy.random import randint
In [9]: df = DataFrame({'a': randint(3, size=10)})
In [10]:
In [10]: df
Out[10]:
a
0 0
1 2
2 0
3 1
4 0
5 0
6 0
7 0
8 0
9 0
In [11]: s = d...
How can javascript upload a blob?
...
You actually don't have to use FormData to send a Blob to the server from JavaScript (and a File is also a Blob).
jQuery example:
var file = $('#fileInput').get(0).files.item(0); // instance of File
$.ajax({
type: 'POST',
url: 'upload.php',
data: file,
contentType: 'application/my-b...
How to get existing fragments when using FragmentPagerAdapter
...create Fragments for your ViewPager, but upon Activity recreation (whether from a device rotation or the system killing your App to regain memory) these Fragments won't be created again, but instead their instances retrieved from the FragmentManager. Now say your Activity needs to get a reference to...
Flatten an irregular list of lists
... can use a tuple of str and bytes to get the same effect there.
The yield from operator returns an item from a generator one at a time. This syntax for delegating to a subgenerator was added in 3.3
def flatten(l):
for el in l:
if isinstance(el, collections.Iterable) and not isinstance(...
How to play with Control.Monad.Writer in haskell?
...t has logging capabilities, but also does something else - say it can read from an environment too. You'd implement this as
type RW r w a = ReaderT r (Writer w a)
Now because the writer is inside the ReaderT monad transformer, if you want to log output you can't use tell w (because that only oper...
(![]+[])[+[]]… Explain why this works
...
Where does the "i" come from?
– Josh Stodola
Nov 13 '10 at 5:00
5
...