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Why are private fields private to the type, not the instance?
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I think one reason it works this way is because access modifiers work at compile time. As such, determining whether or not a given object is also the current object isn't easy to do. For example, consider this code:
public class Foo
{
private int bar;
public void Baz(Foo other)
{
...
How many threads is too many?
...rocessing of requests as they arrive as you need to wait for a thread to become available.
That's why you measure. As you state, the vast majority of your threads will be waiting for a response from the database so they won't be running. There are two factors that affect how many threads you should...
std::string formatting like sprintf
...ave write access to the underlying buffer (until C++11; see Dietrich Epp's comment). You'll have to do it first in a c-string, then copy it into a std::string:
char buff[100];
snprintf(buff, sizeof(buff), "%s", "Hello");
std::string buffAsStdStr = buff;
But I'm not sure why you wouldn't jus...
What algorithm can be used for packing rectangles of different sizes into the smallest rectangle pos
...ck and dirty first pass solution is always a great one to start with, as a comparison if nothing else.
Greedy placement from large to small.
Put the largest rectangle remaining into your packed area. If it can't fit anywhere, place it in a place that extends the pack region as little as possible. ...
Quickly reading very large tables as dataframes
...t nrows=the number of records in your data (nmax in scan).
Make sure that comment.char="" to turn off interpretation of comments.
Explicitly define the classes of each column using colClasses in read.table.
Setting multi.line=FALSE may also improve performance in scan.
If none of these thing wo...
Add Keypair to existing EC2 instance
... I wanted to capture the information in the link that Rodney posted on his comment.
Credit goes to Eric Hammond for this information.
Fixing Files on the Root EBS Volume of an EC2 Instance
You can examine and edit files on the root EBS volume on an EC2 instance even if you are in what you conside...
Generate a random point within a circle (uniformly)
...a distance x+y from the origin. If x+y>R we fold back down.
Here's the complete algorithm for R=1. I hope you agree it's pretty simple. It uses trig, but you can give a guarantee on how long it'll take, and how many random() calls it needs, unlike rejection sampling.
t = 2*pi*random()
u = rando...
Can we define implicit conversions of enums in c#?
... declaring a normal enum (though you can refactor some of the above into a common generic base class). You can go even further by having the base class implement IComparable & IEquatable, as well as adding methods to return the value of DescriptionAttributes, declared names, etc, etc.
I wrote a...
How to use HTML to print header and footer on every printed page of a document?
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Simple Digit Recognition OCR in OpenCV-Python
...rposes).
1) My first question was about letter_recognition.data file that comes with OpenCV samples. I wanted to know what is inside that file.
It contains a letter, along with 16 features of that letter.
And this SOF helped me to find it. These 16 features are explained in the paperLetter Recogn...