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(Built-in) way in JavaScript to check if a string is a valid number

...ic example you gave: function isNumeric(num){ return !isNaN(num) } To convert a string containing a number into a number: Only works if the string only contains numeric characters, else it returns NaN. +num // returns the numeric value of the string, or NaN /...
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Get decimal portion of a number with JavaScript

... You could convert to string, right? n = (n + "").split("."); share | improve this answer | follow ...
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Python - When to use file vs open

...as requested in the mode arg. I especially feel this way when the obvious intent of the devs back then was 2 retain open4compat. – umeboshi Sep 21 '13 at 17:35 add a comment ...
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How do I do base64 encoding on iOS?

...c(intLength, sizeof(unsigned char)); // Run through the whole string, converting as we go while ( ((intCurrent = *objPointer++) != '\0') && (intLength-- > 0) ) { if (intCurrent == '=') { if (*objPointer != '=' && ((i % 4) == 1)) {// || (intLength > ...
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Why does a function with no parameters (compared to the actual function definition) compile?

... Arrays and functions are not passed to functions, but are automatically converted to pointers. If the list is terminated with an ellipsis (,...), then there is no set number of parameters. Note: the header stdarg.h can be used to access arguments when using an ellipsis. And again for the ...
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In Docker, what's the difference between a container and an image? [duplicate]

... dev etc home lib lib64 media mnt opt proc root run sbin srv sys tmp usr var root@48cff2e9be75:/# cat > foo This is a really important file!!!! root@48cff2e9be75:/# exit Don't expect that file to stick around when you exit and restart the image. You're restarting from exactly t...
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How do I iterate over a range of numbers defined by variables in Bash?

... ((i=1;i<=100000;++i)); do :; done real 0m21.220s user 0m19.763s sys 0m1.203s $ time for i in $(eval echo "{1..100000}"); do :; done; real 0m13.881s user 0m13.536s sys 0m0.152s – Marcin Zaluski Jul 4 '12 at 14:55 ...
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How to read json file into java with simple JSON library

... You can use jackson library and simply use these 3 lines to convert your json file to Java Object. ObjectMapper mapper = new ObjectMapper(); InputStream is = Test.class.getResourceAsStream("/test.json"); testObj = mapper.readValue(is, Test.class); ...
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error: cannot dynamic_cast ‘b’ (of type ‘class Base*’) to type ‘c...

...以将析构函数设置为虚函数. 更正后的代码为(来自: c++ - converting a base class pointer to a derived class pointer): #include <iostream> using namespace std; class Base { public: Base() {}; virtual ~Base() {}; // make it polymorphic }; template<class T> class ...
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How do I print the type or class of a variable in Swift?

... As of Xcode 6.3 with Swift 1.2, you can simply convert type values into the full demangled String. toString(Int) // "Swift.Int" toString(Int.Type) // "Swift.Int.Type" toString((10).dynamicType) // "Swift.Int" println(Bool.self) ...