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Apply a function to every row of a matrix or a data frame
... variable before using vapply/sapply/ apply is good practice as it reduces time a lot. Let's see microbenchmark results
a = data.frame(t(iris[1:10,1:3]))
b = iris[1:10,1:3]
microbenchmark::microbenchmark(
apply(b, 1 , prod),
vapply(a, prod, 0),
sapply(a, prod) ,
apply(iris[1:10,1:3...
Save the console.log in Chrome to a file
...ropriately, can handle nested objects and arrays, and can optionally put a timestamp next to each log. You can also toggle live-logging in one place, and without having to remove all your logging statements.
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Finding ALL duplicate rows, including “elements with smaller subscripts”
...m currently using isn't big enough to make tests which produce significant time gaps.
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Is it possible to serialize and deserialize a class in C++?
...ata (almost none). boost::serialization becomes really annoying when every time you open an archive, it writes its lib version to the stream, which makes appending to a file impossible.
– CyberSnoopy
Aug 5 '14 at 5:52
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What is the best data type to use for money in C#?
...er range, but greater precision - so you don't lose all those pennies over time!
Full details here:
http://msdn.microsoft.com/en-us/library/364x0z75.aspx
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How to get the build/version number of your Android application?
...'s not very reliable. Version name shows up as an empty string most of the time.
– Binoy Babu
Dec 13 '14 at 15:50
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Check if a variable is of function type
...n - the instanceof operator has been supported in browsers for a very long time, so don't worry - it will work in IE 6.
Next best way is:
function foo(v) {if (typeof v === "function") {/* do something */} };
disadvantage of typeof is that it is susceptible to silent failure, bad, so if you hav...
EF Migrations: Rollback last applied migration?
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You don't need to include the date/time. You can just put in the name.
– Richard Marskell - Drackir
Jan 26 '18 at 19:53
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Traverse all the Nodes of a JSON Object Tree with JavaScript
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@jasdeepkhalsa: That true. But at the time of the writing of the answer jshint wasn't even started as a project for one and a half year.
– TheHippo
Jul 3 '15 at 17:14
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Android: combining text & image on a Button or ImageButton
... on a button and add dynamically, depending on what's happening during run-time, some text above/over the image.
17 Answers...