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String concatenation vs. string substitution in Python

...catenation is (significantly) faster according to my machine. But stylistically, I'm willing to pay the price of substitution if performance is not critical. Well, and if I need formatting, there's no need to even ask the question... there's no option but to use interpolation/templating. >>&g...
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MPICH vs OpenMPI

...xtensive optimizations that make it the preferred implementation in nearly all cases. Feature Support from the Latest MPI Standard An orthogonal axis to hardware/platform support is coverage of the MPI standard. Here MPICH is usually far and away superior. MPICH has been the first implementation...
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How to append rows to an R data frame

... Not knowing what you are trying to do, I'll share one more suggestion: Preallocate vectors of the type you want for each column, insert values into those vectors, and then, at the end, create your data.frame. Continuing with Julian's f3 (a preallocated data.frame) as the fastest option so far, def...
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How to access the first property of a Javascript object?

...ject.keys return order is not guaranteed as per ECMAScript however unofficially it is by all major browsers implementations, please read https://stackoverflow.com/a/23202095 for details on this. share | ...
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Where are iOS simulator screenshots stored?

... For me, there's nothing in that folder. It's all on the Desktop. Not sure why? :/ – chakrit Feb 9 '12 at 6:21 ...
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Efficiency of purely functional programming

...ssible asymptotic slowdown that can happen when programming purely functionally as opposed to imperatively (i.e. allowing side-effects)? ...
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Chrome Uncaught Syntax Error: Unexpected Token ILLEGAL [duplicate]

...e error in Chrome after pasting code copied from jsfiddle. If you select all the code from a panel in jsfiddle and paste it into the free text editor Notepad++, you should be able to see the problem character as a question mark "?" at the very end of your code. Delete this question mark, then copy...
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How can I make the tabs work normally on Xcode 4?

Xcode finally added tabs but the problem is that they behave very strange. For example they will keep a tab open only if it was opened to a new tab. ...
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How to tell if a string contains a certain character in JavaScript?

...tion does. There are a lot of people who don't understand regex, and generally the simpler answer is the best. – kemiller2002 Oct 13 '15 at 19:19 ...
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What is LINQ and what does it do? [closed]

...eries against many targets (databases, in-memory objects, XML) with practically no consideration of the underlying way in which the query will be executed. Let's start this exploration with the parts belonging to the .NET Framework (3.5). LINQ To Objects - examine System.Linq.Enumerable for query...