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How to read data when some numbers contain commas as thousand separator?
...u can have read.table or read.csv do this conversion for you semi-automatically. First create a new class definition, then create a conversion function and set it as an "as" method using the setAs function like so:
setClass("num.with.commas")
setAs("character", "num.with.commas",
function(...
Difference between volatile and synchronized in Java
...om obtaining the monitor (or lock) for the same object, thereby preventing all code blocks protected by synchronization on the same object from executing concurrently. Synchronization also creates a "happens-before" memory barrier, causing a memory visibility constraint such that anything done up t...
How to succinctly write a formula with many variables from a data frame?
...
There is a special identifier that one can use in a formula to mean all the variables, it is the . identifier.
y <- c(1,4,6)
d <- data.frame(y = y, x1 = c(4,-1,3), x2 = c(3,9,8), x3 = c(4,-4,-2))
mod <- lm(y ~ ., data = d)
You can also do things like this, to use all variables but...
Detecting value change of input[type=text] in jQuery
...query-keyup-doesnt-work-with-keycode-filtering?noredirect=1#comment38213480_24651811
This solution helped me to progress on my project.
$("#your_textbox").on("input propertychange",function(){
// Do your thing here.
});
Note: propertychange for lower versions of IE.
...
How to implement an abstract class in ruby?
I know there is no concept of abstract class in ruby. But if at all it needs to be implemented, how to go about it? I tried something like...
...
What is the 'pythonic' equivalent to the 'fold' function from functional programming?
...(xs):
return reduce(operator.mul, xs, 1)
Be aware that reduce is actually a foldl, in Haskell terms. There is no special syntax to perform folds, there's no builtin foldr, and actually using reduce with non-associative operators is considered bad style.
Using higher-order functions is quite p...
Bitwise operation and usage
...Bitwise operators are operators that work on multi-bit values, but conceptually one bit at a time.
AND is 1 only if both of its inputs are 1, otherwise it's 0.
OR is 1 if one or both of its inputs are 1, otherwise it's 0.
XOR is 1 only if exactly one of its inputs are 1, otherwise it's 0.
NOT is 1...
jQuery deferreds and promises - .then() vs .done()
...n't see the difference between using .then() & .done() for successful callbacks. I know Eric Hynds mentions that .done() and .success() map to the same functionality but I'm guessing so does .then() as all the callbacks are all invoked on a completion of a successful operation.
...
How do I disable “missing docstring” warnings at a file-level in Pylint?
... have a separate code for the various place where docstrings can occur, so all you can do is disable C0111. The problem is that if you disable this at module scope, then it will be disabled everywhere in the module (i.e you won't get any C line for missing function / class / method docstring. Which ...
How do I dump an object's fields to the console?
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Adding an inspect method to your class allows you to define how the class' attributes are displayed, rather than rely on default output. A lot of classes don't implement it well, but it can be really useful when debugging. Ruby will fall back to to_s if it can't f...