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Check if the number is integer
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does the tolerance-checking suggestion really work?? x <- 5-1e-8; x%%1 gives 0.9999999 (which would imply if tol==1e-5 for example) that x is not an integer.
– Ben Bolker
Jan 24 '14 at 15:34
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How to get the number of characters in a std::string?
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If you're using a std::string, call length():
std::string str = "hello";
std::cout << str << ":" << str.length();
// Outputs "hello:5"
If you're using a c-string, call strlen().
const char *str = "hello";
std::cout << str <&lt...
How can I get enum possible values in a MySQL database?
...want to populate my dropdowns with enum possible values from a DB automatically. Is this possible in MySQL?
24 Answers
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Javascript How to define multiple variables on a single line?
...; var a = b = c = [];
>>> c.push(1)
[1]
>>> a
[1]
They all refer to the same object in memory, they are not "unique" since anytime you make a reference to an object ( array, object literal, function ) it's passed by reference and not value. So if you change just one of those vari...
Why does pycharm propose to change method to static
...is because the method does not use self in its body and hence does not actually change the class instance. Hence the method could be static, i.e. callable without passing a class instance or without even having created a class instance.
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When to use next() and return next() in Node.js
... return next() is to ensure that the execution stops after triggering the callback.
If you don't do it, you risk triggering the callback a second time later, which usually has devastating results. Your code is fine as it is, but I would rewrite it as:
app.get('/users/:id?', function(req, res, next...
OAuth 2.0: Benefits and use cases — why?
... 1 is that it requires both the server and clients to sort and sign identically. This is fiddly code and either it's right or you get 401 Unauthorized with little help. This increases the barrier to writing a client.
By requiring the authorization request to run over SSL, OAuth 2.0 removes the need...
Maximum number of characters using keystrokes A, Ctrl+A, Ctrl+C and Ctrl+V
...rough for i up to n, doing two things: pressing A once and pressing select all + copy followed by paste j times (actually j-i-1 below; note the trick here: the contents are still in the clipboard, so we can paste it multiple times without copying each time). We only have to consider up to 4 consecut...
How do I toggle an element's class in pure JavaScript?
... Thank you so much! It's working now :) I add more option for loop: var All = document.querySelectorAll('.menu'); for (var i = 0; i < All.length; i++){ All[i].classList.toggle('hidden-phone'); }
– Blue Tram
Feb 1 '19 at 3:52
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How do you pass arguments to define_method?
... your defined method accepts arguments. When you define a method you're really just nicknaming the block and keeping a reference to it in the class. The parameters come with the block. So:
define_method(:say_hi) { |other| puts "Hi, " + other }
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