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How to check a not-defined variable in JavaScript
...ue for things that don't exist, undefined. The DOM returns null for almost all cases where it fails to find some structure in the document, but in JavaScript itself undefined is the value used.
Second, no, there is not a direct equivalent. If you really want to check for specifically for null, do:
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Is it possible to force Excel recognize UTF-8 CSV files automatically?
...s. The application always uses UTF-8 because of its multilingual nature at all levels. But opening such CSV files (containing e.g. diacritics, cyrillic letters, Greek letters) in Excel does not achieve the expected results showing something like Г„/Г¤, Г–/Г¶ . And I don't know how to forc...
Tricks to manage the available memory in an R session
...lp list in 2004] to list (and/or sort) the largest objects and to occassionally rm() some of them. But by far the most effective solution was ... to run under 64-bit Linux with ample memory.
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Convert SVG image to PNG with PHP
I'm working on a web project that involves a dynamically generated map of the US coloring different states based on a set of data.
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How to do exponentiation in clojure?
...d recommend using this rather than going via Java interop since it handles all the Clojure arbitrary-precision number types correctly. It is in namespace clojure.math.numeric-tower.
It's called expt for exponentiation rather than power or pow which maybe explains why it's a bit hard to find ... any...
How to clone all remote branches in Git?
..., StackOverflow has grown quite a bit in terms of quality.
This "answer" really does not address the question at all. In fact, few of the top-voted answers do.
Here are two answers that will work as of git v2.28.0:
https://stackoverflow.com/a/4754797/430062
https://stackoverflow.com/a/7216269/43006...
Strip spaces/tabs/newlines - python
I am trying to remove all spaces/tabs/newlines in python 2.7 on Linux.
7 Answers
7
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jQuery get mouse position within an element
...entOffset = $(this).parent().offset();
//or $(this).offset(); if you really just want the current element's offset
var relX = e.pageX - parentOffset.left;
var relY = e.pageY - parentOffset.top;
});
share
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How can I eliminate slow resolving/loading of localhost/virtualhost (a 2-3 second lag) on Mac OS X L
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I had the exact same problem and it was driving me crazy!
Put all your hosts file entries for localhost into one line like so:
127.0.0.1 localhost myproject.dev myotherproject.dev
::1 localhost
fe80::1%lo0 localhost
Worked like a charm for me. Seems like a bug in Lion.
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Make a link open a new window (not tab) [duplicate]
... @JeanGkol I rewrote my answer to clarify the issue. Technically, it is working, because it opens a new browsing context (like it is supposed to do). The problem is, that in modern browsers "browsing context" is a tab instead of a window (you can change this in the settings though).
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