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Why is pow(a, d, n) so much faster than a**d % n?
...was taking so long (> 20 seconds) for midsize numbers (~7 digits). I eventually found the following line of code to be the source of the problem:
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Immutable vs Mutable types
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Almost, but not exactly. Technically, all variables are passed by reference in Python, but have a semantics more like pass by value in C. A counterexample to your analogy is if you do def f(my_list): my_list = [1, 2, 3]. With pass-by-reference in C, the val...
SQL exclude a column using SELECT * [except columnA] FROM tableA?
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If you don't want to write each column name manually you can use Script Table As by right clicking on table or view in SSMS like this:
Then you will get whole select query in New Query Editor Window then remove unwanted column like this:
Done
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What is the difference between String.Empty and “” (empty string)?
...ich makes string.Empty more efficient.
In version 2.0 and later of .NET, all occurrences of "" refer to the same string literal, which means "" is equivalent to .Empty, but still not as fast as .Length == 0.
.Length == 0 is the fastest option, but .Empty makes for slightly cleaner code.
See the ...
Node.js Error: Cannot find module express
...arting my app as a normal user, but when starting my app and a system init script it wouldn't work. I fixed it by installing winston locally in the app directory (and adding it to package.json).
– trusktr
Apr 21 '14 at 2:08
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Altering column size in SQL Server
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For most things, I prefer scripting. But for column changes, I like the UI. Don't have to remember to check for NOT NULL or any calculations or any additional column properties. Just click Save (after you make the settings change in SSMS as @7anner no...
Is there a NumPy function to return the first index of something in an array?
...:
itemindex = numpy.where(array==item)
The result is a tuple with first all the row indices, then all the column indices.
For example, if an array is two dimensions and it contained your item at two locations then
array[itemindex[0][0]][itemindex[1][0]]
would be equal to your item and so woul...
Adding new column to existing DataFrame in Python pandas
... because if you have multiple rows, and you use the assignment, it assigns all rows of the new column with that value ( in your case e) which is usually undesirable.
– Paniz
Apr 27 '19 at 22:42
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Making a Sass mixin with optional arguments
...erything simple to read and understand for when you have to come back to a script. thnx Drops.
– Plentybinary
Mar 16 '15 at 19:59
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How to check if mysql database exists
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If you are looking for a php script see below.
$link = mysql_connect('localhost', 'mysql_user', 'mysql_password');
if (!$link) {
die('Not connected : ' . mysql_error());
}
// make foo the current db
$db_selected = mysql_select_db('foo', $link);
if (!...