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Using bitwise OR 0 to floor a number

...number. Math.trunc(13.37) // 13 Math.trunc(42.84) // 42 Math.trunc(0.123) // 0 Math.trunc(-0.123) // -0 Math.trunc("-1.123")// -1 Math.trunc(NaN) // NaN Math.trunc("foo") // NaN Math.trunc() // NaN sh...
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Regex Named Groups in Java

...atching Strings with Balanced Parentheses slide) Example: String: "TEST 123" RegExp: "(?<login>\\w+) (?<id>\\d+)" Access matcher.group(1) ==> TEST matcher.group("login") ==> TEST matcher.name(1) ==> login Replace matcher.replaceAll("aaaaa_$1_sssss_$2____") ==> aaa...
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Javascript equivalent of Python's zip function

...mple: _tarrin = [0..constructor, function(){}, false, undefined, '', 100, 123.324, 2343243243242343242354365476453654625345345, 'sdf23423dsfsdf', 'sdf2324.234dfs','234,234fsf','100,100','100.100'] _parseInt = function(i){return parseInt(i);} _tarrout = _tarrin.map(_parseInt) _tarr...
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Which equals operator (== vs ===) should be used in JavaScript comparisons?

...n the third rule) Now it becomes interesting: var a = "12" + "3"; var b = "123"; alert(a === b); // returns true, because strings behave like value types But how about this?: var a = new String("123"); var b = "123"; alert(a === b); // returns false !! (but they are equal and of the same type) I...
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Summarizing multiple columns with dplyr? [duplicate]

...brary(dplyr) library(purrrlyr) library(data.table) library(bench) set.seed(123) n <- 10000 df <- data.frame( a = sample(1:5, n, replace = TRUE), b = sample(1:5, n, replace = TRUE), c = sample(1:5, n, replace = TRUE), d = sample(1:5, n, replace = TRUE), grp = sample(1:3, n, replac...
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Retrieving parameters from a URL

... import urlparse url = 'http://example.com/?q=abc&p=123' par = urlparse.parse_qs(urlparse.urlparse(url).query) print par['q'][0], par['p'][0] share | improve this answer ...
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Map vs Object in JavaScript

...d Symbol keys where as Maps support more or less any key type. If I do obj[123] = true and then Object.keys(obj) then I will get ["123"] rather than [123]. A Map would preserve the type of the key and return [123] which is great. Maps also allow you to use Objects as keys. Traditionally to do this y...
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C++ protobuf使用入门实例 - C/C++ - 清泛网 - 专注C/C++及内核技术

...ze------ google::protobuf::TestValue msg_val; msg_val.set_number_value(123.f); std::string str = msg_val.SerializeAsString(); std::cout << "--------- len:" << str.length() << ":" << str << std::endl; google::protobuf::Test message; message.mutable_fields()->operator []("test") = msg_va...
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Write a number with two decimal places SQL server

...ters to display, and the number of decimal places to display Select Str(12345.6789, 12, 3) displays: ' 12345.679' ( 3 spaces, 5 digits 12345, a decimal point, and three decimal digits (679). - it rounds if it has to truncate, (unless the integer part is too large for the total size, in whic...
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How to format numbers as currency string?

... id="x"&amp;gt;(press button to get output)&amp;lt;/p&amp;gt; Use it like so: (123456789.12345).formatMoney(2, ".", ","); If you're always going to use '.' and ',', you can leave them off your method call, and the method will default them for you. (123456789.12345).formatMoney(2); If your culture h...