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Javascript seconds to minutes and seconds
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To get the number of full minutes, divide the number of total seconds by 60 (60 seconds/minute):
var minutes = Math.floor(time / 60);
And to get the remaining seconds, multiply the full minutes with 60 and subtract from the total seconds:
var seconds = time - minutes * 60;
Now if ...
How to Calculate Execution Time of a Code Snippet in C++
I have to compute execution time of a C++ code snippet in seconds. It must be working either on Windows or Unix machines.
1...
Length of generator output [duplicate]
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gen = (i for i in data*1000); t0 = monotonic(); len(list(gen))
('list, sec', 1.9684218849870376)
2: test_list_compr.py:8: 0.867 KiB
gen = (i for i in data*1000); t0 = monotonic(); len([i for i in gen])
('list_compr, sec', 2.5885991149989422)
3: test_sum.py:8: 0.859 KiB
gen = (i for i in da...
HTTP headers in Websockets client API
...e client/browser to send. The HTTP path ("GET /xyz") and protocol header ("Sec-WebSocket-Protocol") can be specified in the WebSocket constructor.
The Sec-WebSocket-Protocol header (which is sometimes extended to be used in websocket specific authentication) is generated from the optional second ar...
What is the most efficient/elegant way to parse a flat table into a tree?
...Closure Table in my presentation Models for Hierarchical Data with SQL and PHP and in my book SQL Antipatterns: Avoiding the Pitfalls of Database Programming.
CREATE TABLE ClosureTable (
ancestor_id INT NOT NULL REFERENCES FlatTable(id),
descendant_id INT NOT NULL REFERENCES FlatTable(id),
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Retrieving the last record in each group - MySQL
...d = p2.maxpostid)
WHERE p1.owneruserid = 20860;
1 row in set (1 min 17.89 sec)
Even the EXPLAIN analysis takes over 16 seconds:
+----+-------------+------------+--------+----------------------------+-------------+---------+--------------+---------+-------------+
| id | select_type | table |...
What is cardinality in MySQL?
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The second paragraph is important if you try to understand when it makes sense to index a column.
– VMC
Jun 12 '17 at 14:53
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Position of least significant bit that is set
...2f, result = %d\n",
(end_time - start_time) / (double)(CLOCKS_PER_SEC), result);
start_time = clock();
result = find_first_bits_de_bruijn(nums);
end_time = clock();
printf("De Bruijn multiply. Time = %.2f, result = %d\n",
(end_time - start_time) / (double)(CLOCKS_P...
“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...005, but there's no progress or plan as far as I know. bugs.mysql.com/bug.php?id=9018
– Bill Karwin
Jul 16 '12 at 2:23
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Linking to an external URL in Javadoc?
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/**
* See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.1">HTTP/1.1 documentation</a>}.
*/
public static final String ACCEPT = "Accept";
/**
* See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.2">HTTP/1.1 documentat...