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Meaning of epsilon argument of assertEquals for double values

...nal double DELTA = 1e-15; @Test public void testDelta(){ assertEquals(123.456, 123.456, DELTA); } If you're using hamcrest assertions, you can just use the standard equalTo() with two doubles (it doesn't use a delta). However if you want a delta, you can just use closeTo() (see javadoc), e.g....
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How to validate phone numbers using regex

...ou should discard the (0) entirely). Then, you end up with values like: 12345678901 12345678901x1234 345678901x1234 12344678901 12345678901 12345678901 12345678901 +4112345678 +441234567890 Then when you display, reformat to your hearts content. e.g. 1 (234) 567-8901 1 (234) 567-89...
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A numeric string as array key in PHP

Is it possible to use a numeric string like "123" as a key in a PHP array, without it being converted to an integer? 11 A...
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What is the 'dynamic' type in C# 4.0 used for?

...'ve been using C# so long that it just feels "wrong" to me. dynamic foo = 123; foo = "bar"; OK, so you most likely will not be writing code like the above very often. There may be times, however, when variable reuse can come in handy or clean up a dirty piece of legacy code. One simple case I run...
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How do you round to 1 decimal place in Javascript?

...turn Math.round(value * multiplier) / multiplier; } ... usage ... round(12345.6789, 2) // 12345.68 round(12345.6789, 1) // 12345.7 ... defaults to round to nearest whole number (precision 0) ... round(12345.6789) // 12346 ... and can be used to round to nearest 10 or 100 etc... round(12345....
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Why would I ever use push_back instead of emplace_back?

... will be invalid after the call. std::vector<int> v; v.emplace_back(123); v.emplace_back(v[0]); // Produces incorrect results in some compilers On one compiler, v contains the values 123 and 21 instead of the expected 123 and 123. This is due to the fact that the 2nd call to emplace_back re...
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Parse query string into an array

...alone is note accurate, it could display for example: $url = "somepage?id=123&lang=gr&size=300"; parse_str() would return: Array ( [somepage?id] => 123 [lang] => gr [size] => 300 ) It would be better to combine parse_str() with parse_url() like so: $url = "som...
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Why does isNaN(“ ”) (string with spaces) equal false?

... But parseInt("123abcd") returns 123, which means isNaN(parseInt("123abcd")) will return false while it should return true! – Pawan Nogariya Dec 27 '12 at 6:23 ...
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How can I print the contents of a hash in Perl?

... Data::Dumper is your friend. use Data::Dumper; my %hash = ('abc' => 123, 'def' => [4,5,6]); print Dumper(\%hash); will output $VAR1 = { 'def' => [ 4, 5, 6 ], 'abc' => 123 ...
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What is the difference between parseInt() and Number()?

... typeof parseInt("123") => number typeof Number("123") => number typeof new Number("123") => object (Number primitive wrapper object) first two will give you better performance as it returns a primitive instead of an object. ...