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PostgreSQL database default location on Linux
... server.
The location of the data directory depends on the distribution. If you install from source, the default is /usr/local/pgsql/data:
In file system terms, a database
cluster will be a single directory
under which all data will be stored.
We call this the data directory or
data ar...
submitting a GET form with query string params and hidden params disappear
... browser retaining any existing query string in the action URL.
As the specifications (RFC1866, page 46; HTML 4.x section 17.13.3) state:
If the method is "get" and the action is an HTTP URI, the user agent takes the value of action, appends a `?' to it, then appends the form data set, encoded usin...
Should I store entire objects, or pointers to objects in containers?
...
Since people are chiming in on the efficency of using pointers.
If you're considering using a std::vector and if updates are few and you often iterate over your collection and it's a non polymorphic type storing object "copies" will be more efficent since you'll get better locality of ref...
Pickle incompatibility of numpy arrays between Python 2 and 3
...ject, which is assumed to be ASCII, while in this case it is binary data. If this is a bug in the Python 3 unpickler, or a "misuse" of the pickler by numpy, I don't know.
Here is something of a workaround, but I don't know how meaningful the data is at this point:
import pickle
import gzip
import...
Modulo operation with negative numbers
...mple A. 5/(-3) is -1
=> (-1) * (-3) + 5%(-3) = 5
This can only happen if 5%(-3) is 2.
Example B. (-5)/3 is -1
=> (-1) * 3 + (-5)%3 = -5
This can only happen if (-5)%3 is -2
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impr...
What's the difference between an argument and a parameter?
...n a method definition" but it might be better to say "method declaration" [if someone is making a distinction between 'declaration' and 'definition']
– nandan
Jan 24 '14 at 21:05
1...
Test if a variable is set in bash when using “set -o nounset”
...
#!/bin/bash
set -o nounset
VALUE=${WHATEVER:-}
if [ ! -z ${VALUE} ];
then echo "yo"
fi
echo "whatever"
In this case, VALUE ends up being an empty string if WHATEVER is not set. We're using the {parameter:-word} expansion, which you can look up in man bash under "Param...
How can I calculate the difference between two dates?
...ts will always be time-zone-agnostic.
Furthermore, this documentation specifies that Cocoa's implementation of time does not account for leap seconds, so if you require such accuracy, you will need to roll your own implementation.
...
Simplest way to wait some asynchronous tasks complete, in Javascript?
...callback) {
conn.collection(name).drop(function(err) {
if (err)
return callback(err);
console.log('dropped');
callback(null, name);
});
}
)});
async.parallel(calls, function(err, result) {
/* this code will run after all ca...
What is the use of making constructor private in a class?
...
@Will: Not if you use reflection. Declaring constructors private is intended to prevent instantiation (barring reflection), but preventing subclassing is a side effect, not the intent. The appropriate tool for this is declaring the cla...