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Why does X[Y] join of data.tables not allow a full outer join, or a left join?
...context of each group. Let's say foo is in X, and bar is in Y (along with 20 other columns in Y). Isn't X[Y,sum(foo*bar)] quicker to program and quicker to run than a merge of everything wastefully followed by a subset?
If you want a left outer join of X[Y]
le <- Y[X]
mallx <- merge(X, ...
How to detect Safari, Chrome, IE, Firefox and Opera browser?
...sion. Use feature detection when possible.
Demo: https://jsfiddle.net/6spj1059/
// Opera 8.0+
var isOpera = (!!window.opr && !!opr.addons) || !!window.opera || navigator.userAgent.indexOf(' OPR/') >= 0;
// Firefox 1.0+
var isFirefox = typeof InstallTrigger !== 'undefined';
// Safari...
Convert list to tuple in Python
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30
You might have done something like this:
>>> tuple = 45, 34 # You used `tuple` as a v...
MySQL Select minimum/maximum among two (or more) given values
... use LEAST and GREATEST function to achieve it.
SELECT
GREATEST(A.date0, B.date0) AS date0,
LEAST(A.date1, B.date1) AS date1
FROM A, B
WHERE B.x = A.x
Both are described here http://dev.mysql.com/doc/refman/5.0/en/comparison-operators.html
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What is the best way to tell if a character is a letter or number in Java without using regexes?
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answered Oct 28 '10 at 23:06
AdamAdam
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How can I change the current URL?
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answered Oct 2 '10 at 18:10
glebmglebm
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How to implement WiX installer upgrade?
...
In the newest versions (from the 3.5.1315.0 beta), you can use the MajorUpgrade element instead of using your own.
For example, we use this code to do automatic upgrades. It prevents downgrades, giving a localised error message, and also prevents upgrading an alread...
Redirect to named url pattern directly from urls.py in django?
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edited Oct 3 '16 at 10:37
Flimm
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answe...
How to use greater than operator with date?
...se backtick instead
SELECT * FROM `la_schedule` WHERE `start_date` > '2012-11-18';
SQLFiddle Demo
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What is the difference between save and export in Docker?
...h images.
An image has to be considered as 'dead' or immutable, starting 0 or 1000 containers from it won't alter a single byte. That's why I made a comparison with a system install ISO earlier. It's maybe even closer to a live-CD.
A container "boots" the image and adds an additional layer on top ...