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How to convert byte array to string and vice versa?
... This might work, but you should avoid using String constructor at all cost.
– hfontanez
Jun 26 '17 at 17:13
t...
Why are #ifndef and #define used in C++ header files?
...he header is included, it checks if a unique value (in this case HEADERFILE_H) is defined. Then if it's not defined, it defines it and continues to the rest of the page.
When the code is included again, the first ifndef fails, resulting in a blank file.
That prevents double declaration of any iden...
Vim: Replacing a line with another one yanked before
... If you overwrite additional lines with ccCTRL+r0ESC instead of V"0p then all following lines can be replaced with just . (the repeater)
– Jordan Morris
Aug 26 '13 at 5:10
...
How do I print a double value with full precision using cout?
...
Is the really the right answer? When I manually use a high number, I can print out as many as 51 digits of approximated e, but with cout.precision(numeric_limits<double>::digits10 + 2); I only get 16....
– ...
Class vs. static method in JavaScript
... instantiate an object from that function using the new keyword which will allow you to create something similar to a class in a standard OOP language.
I'd suggest ignoring __proto__ most of the time because it has poor cross browser support, and instead focus on learning about how prototype works....
EF Migrations: Rollback last applied migration?
This looks like a really common task, but I can't find an easy way to do it.
14 Answers
...
Apply multiple functions to multiple groupby columns
...ion.
I recommend making a single custom function that returns a Series of all the aggregations. Use the Series index as labels for the new columns:
def f(x):
d = {}
d['a_sum'] = x['a'].sum()
d['a_max'] = x['a'].max()
d['b_mean'] = x['b'].mean()
d['c_d_prodsum'] = (x['c'] * x['d...
Reference: mod_rewrite, URL rewriting and “pretty links” explained
...rver doesn't have to be Apache, there are many other web servers which are all just programs which run persistently and are attached to a port which respond to HTTP requests. You can write one yourself. This paragraph was intended to divorce you from any notion that URLs directly equal files, which ...
How to provide user name and password when connecting to a network share
... it in a hurry:
public class NetworkConnection : IDisposable
{
string _networkName;
public NetworkConnection(string networkName,
NetworkCredential credentials)
{
_networkName = networkName;
var netResource = new NetResource()
{
Scope = Reso...
Understanding generators in Python
...A generator is simply a function which returns an object on which you can call next, such that for every call it returns some value, until it raises a StopIteration exception, signaling that all values have been generated. Such an object is called an iterator.
Normal functions return a single value...