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How to prevent gcc optimizing some statements in C?
In order to make a page dirty (switching on the dirty bit in the page table entry), I touch the first bytes of the page like this:
...
Elegant way to check for missing packages and install them?
...}
}
# Then try/install packages...
foo( c("ggplot2" , "reshape2" , "data.table" ) )
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Pandas every nth row
...2nd row it would be df.iloc[1::5, :].
– Little Bobby Tables
Nov 13 '16 at 17:18
17
You can omit t...
Sending HTTP POST Request In Java
...e, using a PrintWriter totally fails.
– Little Bobby Tables
Dec 16 '11 at 8:35
5
and how to set 2...
Differences in boolean operators: & vs && and | vs ||
...ou're talking about the logical meaning of both operators, here you have a table-resume:
boolean a, b;
Operation Meaning Note
--------- ------- ----
a && b logical AND short-circuiting
a || b logical OR ...
How to write a JSON file in C#?
...
@RobertHarvey Liam's Json.Net link has a nice table showing what the differences are. Coming from the people that make it, of course you should take it with a grain of salt, but it is indeed better than the built-in things.
– Tim S.
...
PHP Error handling: die() Vs trigger_error() Vs throw Exception
...ry {
while ($row = gather_data()) {
$db->query('INSERT INTO `table` (`foo`,`bar`) VALUES(?,?)', ...);
}
$db->query('COMMIT');
} catch(Exception $e) {
$db->query('ROLLBACK');
}
Here, if gather_data() just plain croaked (using E_USER_ERROR or die()) there's a chance, ...
Flask-SQLAlchemy import/context issue
... id = db.Column(db.Integer, primary_key=True)
...
# Create the database tables.
db.create_all()
...
# start the flask loop
app.run()
I just splitted one app.py to app.py and model.py without using Blueprint. In that case, the above answer dosen't work. A line code is needed to work.
before:
...
How do I get the current time zone of MySQL?
...alues are not stored with timezone information in MySQL:
mysql> create table foo (tstamp datetime) Engine=MyISAM;
Query OK, 0 rows affected (0.06 sec)
mysql> insert into foo (tstamp) values (now());
Query OK, 1 row affected (0.00 sec)
mysql> set time_zone = '+01:00';
Query OK, 0 rows aff...
Meaning of -
...aracter set that are represented by the values 60 to 65.
Extract of ASCII Table 60-65
╔══════╦══════════════╗
║ Byte ║ Character ║
╠══════╬══════════════║
║ 60 ║ < ║
║ 61 ...