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What is the zero for string?

... NewKey(c, "kind", "", 0, p) From the specification : When memory is allocated to store a value, either through a declaration or a call of make or new, and no explicit initialization is provided, the memory is given a default initialization. Each element of such a value is set to the zer...
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What's the fastest way to merge/join data.frames in R?

...ata.table is actually timing base functions colMeans and cbind (the memory allocation and copying induced by using those functions). There are good and bad ways of using data.table, too. benchmark(replications = 1, order = "elapsed", aggregate = aggregate(d[c("x", "y")], d[c("g1", "g2")], mean),...
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How can I check if a string represents an int, without using try/except?

...o only use it for error trapping and reporting. I was going to gripe that PHP, perl, ruby, C, and even the freaking shell have simple functions for testing a string for integer-hood, but due diligence in verifying those assumptions tripped me up! Apparently this lack is a common sickness. Here'...
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List passed by ref - help me explain this behaviour

... There are two parts of memory allocated for an object of reference type. One in stack and one in heap. The part in stack (aka a pointer) contains reference to the part in heap - where the actual values are stored. When ref keyword is not use, just a copy ...
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What are deferred objects?

...eferred object is resolved or rejected. Deferred In Action: $.get("test.php").done( function(){ alert("$.get succeeded"); } ); $.get("test.php") .done(function(){ alert("$.get succeeded"); }) .fail(function(){ alert("$.get failed!"); }); And it seems that the existing ajax() method ...
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Set padding for UITextField with UITextBorderStyleNone

... view of the size of the padding you want: UIView *paddingView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 5, 20)]; textField.leftView = paddingView; textField.leftViewMode = UITextFieldViewModeAlways; Worked like a charm for me! In Swift 3/ Swift 4, it can be done by doing that let paddin...
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Smooth GPS data

... kalman.sourceforge.net/index.php here is C++ implementation of Kalman filter. – Rostyslav Druzhchenko Aug 21 '14 at 9:04 1 ...
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How can I get a user's media from Instagram without authenticating as a user?

...ccess-Control-Allow-Headers restrictions. It still possible to do this via php or any other server side method with proper signature based on rhx_gis, csrf_token and request parameters. You can read more about it here. JANUARY 2019 UPDATE: YQL retired, so, check my latest update with Google Image P...
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Count with IF condition in MySQL query

...automatically convert NULL to '' when fetching the value. For example with PHP's mysqli interface it would be safe to run your query without COALESCE(). share | improve this answer | ...
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How to get Bitmap from an Uri?

...images, the following code will load it in in tiles (avoiding large memory allocations): BitmapRegionDecoder decoder = BitmapRegionDecoder.newInstance(myStream, false); Bitmap region = decoder.decodeRegion(new Rect(10, 10, 50, 50), null); See the answer here ...