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How to 'insert if not exists' in MySQL?
...count($vars)) {
$table = mysql_real_escape_string($table);
$vars = array_map('mysql_real_escape_string', $vars);
$req = "INSERT INTO `$table` (`". join('`, `', array_keys($vars)) ."`) ";
$req .= "SELECT '". join("', '", $vars) ."' FROM DUAL ";
$req .= "WHERE NOT EXISTS (SELECT 1...
Adding a directory to $LOAD_PATH (Ruby)
... you type script/console in your Rails project and enter $:, you'll get an array that includes all the directories needed to load Ruby. The take-away from this little exercise is that $: is an array. That being so, you can perform functions on it like prepending other directories with the unshift ...
How do I make a matrix from a list of vectors in R?
...
simplify2array is a base function that is fairly intuitive. However, since R's default is to fill in data by columns first, you will need to transpose the output. (sapply uses simplify2array, as documented in help(sapply).)
> t(si...
How to create GUID / UUID?
...-1e11).replace(/[018]/g, c =>
(c ^ crypto.getRandomValues(new Uint8Array(1))[0] & 15 >> c / 4).toString(16)
);
}
console.log(uuidv4());
Update, 2020-01-06: There is a proposal in the works for a standard uuid module as part of the JS language
...
Redis strings vs Redis hashes to represent JSON: efficiency?
...ong available options of storing json blob as an json string or as a byte array in Redis?
– Vinit89
Jul 11 '18 at 11:55
...
What is the difference between the template method and the strategy patterns?
... what exactly will be done on init, run and done.
Example of a strategy:
array.sort (IComparer<T> comparer)
Here, when writing a comparer, you do not inherit from an array. Array delegates the comparison algorithm to a comparer.
...
Save classifier to disk in scikit-learn
...ib.dump and joblib.load which is much more efficient at handling numerical arrays than the default python pickler.
Joblib is included in scikit-learn:
>>> import joblib
>>> from sklearn.datasets import load_digits
>>> from sklearn.linear_model import SGDClassifier
>&...
Java equivalent to Explode and Implode(PHP) [closed]
...rt library does not provide such functionality. You just iterate over your array and build string using StringBuilder/StringBuffer. Or you can try excellent Google Guava Splitter and Joiner or split/join methods from Apache Commons StringUtils.
...
How to use LINQ to select object with minimum or maximum property value
...t. This solution's "slowness" depends on the underlying data. If this is a array or List<T>, then LINQ to Objects has no choice but to sort the entire collection first before selecting the first item. In this case it will be slower than the other solution suggested. However, if this is a LINQ ...
How to make an HTTP POST web request
...ould like to add that the response variable for the POST request is a byte array. In order to get the string response you just do Encoding.ASCII.GetString(response); (using System.Text)
– Sindre
Jan 17 '14 at 19:52
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