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Avoid trailing zeroes in printf()
...ld widths, then format the number using a format string based on that. The test harness main() shows this in action:
40.00000000000000000000 -> 40.000
359.01335000000000263753 -> 359.013
-359.00999000000001615263 -> -359.010
359.00999999999999090505 -> 359.010
3.01357000000000008...
What is the difference between a map and a dictionary?
...lements that can support the insertion and deletion of elements as well as test for membership
For example, we have a set of elements { A, B, C, D... } that we've been able to insert and could start deleting, and we're able to query "is C present?".
The Computing Science notion of map though is b...
Rails layouts per action?
...trollers in many levels. I have used method before, but wasn't thinking of testing that when I had the problem now, thanks again.
– 244an
Oct 1 '15 at 15:07
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How do I update if exists, insert if not (AKA “upsert” or “merge”) in MySQL?
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Note this is not standard SQL. An example from the manual:
CREATE TABLE test (
id INT UNSIGNED NOT NULL AUTO_INCREMENT,
data VARCHAR(64) DEFAULT NULL,
ts TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (id)
);
mysql> REPLACE INTO test VALUES (1, '...
SQL to determine minimum sequential days of access?
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Truncate the CreateionDate down to days in all these tests (on the right side only or you kill SARG) using DATEADD(dd, DATEDIFF(dd, 0, CreationDate), 0) This works by subtracting the supplied date from zero--which Microsoft SQL Server interprets as 1900-01-01 00:00:00 and gives...
What's the difference between the Dependency Injection and Service Locator patterns?
...One important result of this is that the DI example is much easier to unit test -- because you can pass it mock implementations of its dependent objects. You could combine the two -- and inject the service locator (or a factory), if you wanted.
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How to record webcam and audio using webRTC and a server-based Peer connection
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@Redtopia In some recent load tests we were able to get 150 one2one connections of webrtc on an i5/16GB RAM. You can expect that these numbers will be better in the future, but don't expect miracles: there is a lot of encryption going on for SRTP, and tha...
How do you check whether a number is divisible by another number (Python)?
I need to test whether each number from 1 to 1000 is a multiple of 3 or a multiple of 5. The way I thought I'd do this would be to divide the number by 3, and if the result is an integer then it would be a multiple of 3. Same with 5.
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Find rows with multiple duplicate fields with Active Record, Rails & Postgres
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Tested & Working Version
User.select(:first,:email).group(:first,:email).having("count(*) > 1")
Also, this is a little unrelated but handy. If you want to see how times each combination was found, put .size at the e...
Table name as variable
... set the table name based on the current year and month name, in this case TEST_2012OCTOBER. I then check if it exists in the DB already, and remove if it does. Then the next block will use a SELECT INTO Statement to create the table and populate it with records from another table with parameters.
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