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How can the Euclidean distance be calculated with NumPy?
...er too much if you use sqrt-sum with axis=0, linalg.norm with axis=0, or
a_min_b = a - b
numpy.sqrt(numpy.einsum('ij,ij->j', a_min_b, a_min_b))
which is, by a slight margin, the fastest variant. (That actually holds true for just one row as well.)
The variants where you sum up over the second...
How to write an inline IF statement in JavaScript?
...developer.mozilla.org/en-US/docs/JavaScript/Reference/Operators/Conditional_Operator
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How can I get the count of milliseconds since midnight for the current?
... // Get current moment in UTC, then…
.get( ChronoField.MILLI_OF_SECOND ) // interrogate a `TemporalField`.
2017-04-25T03:01:14.113Z → 113
Get the fractional second in nanoseconds (billions).
Divide by a thousand to truncate to milliseconds (thousands).
See this code run l...
Invalid argument supplied for foreach()
...s to be the most clean - not sure if it's the most efficient, mind!
if (is_array($values) || is_object($values))
{
foreach ($values as $value)
{
...
}
}
The reason for my preference is it doesn't allocate an empty array when you've got nothing to begin with anyway.
...
Swift - encode URL
... it will encode some characters that do not need to be encoded (like -, ., _ or ~ -– see 2.3. Unreserved characters in RFC 3986). I find using .alphanumerics simpler than constructing a custom character set and do not mind some additional characters to be encoded. If that bothers you, construct a ...
How do I see what character set a MySQL database / table / column is?
...'d do it -
For Schemas (or Databases - they are synonyms):
SELECT default_character_set_name FROM information_schema.SCHEMATA
WHERE schema_name = "schemaname";
For Tables:
SELECT CCSA.character_set_name FROM information_schema.`TABLES` T,
information_schema.`COLLATION_CHARACTER_SET_APPL...
PHP array delete by value (not key)
...
Using array_search() and unset, try the following:
if (($key = array_search($del_val, $messages)) !== false) {
unset($messages[$key]);
}
array_search() returns the key of the element it finds, which can be used to remove that ele...
String comparison using '==' vs. 'strcmp()'
...tring2 sorts before string1 or 0 if they are the same. For example $string_first = "aabo"; $string_second = "aaao"; echo $n = strcmp($string_first,$string_second); will return greater than zero, as aaao is sorting before aabo.
– HTML Man
Aug 16 '13 at 18:00
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How to find out the MySQL root password
...sword.
On ubuntu I did the following:
sudo service mysql stop
sudo mysqld_safe --skip-grant-tables --skip-syslog --skip-networking
Then run mysql in a new terminal:
mysql -u root
And run the following queries to change the password:
UPDATE mysql.user SET authentication_string=PASSWORD('passw...
How to print out more than 20 items (documents) in MongoDB's shell?
...h(function(f){print(tojson(f, '', true));});
which would return only the _id and name field from foo.
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