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Why is null an object and what's the difference between null and undefined?
...n short; undefined is where no notion of the thing exists; it has no type, and it's never been referenced before in that scope; null is where the thing is known to exist, but it's not known what the value is.
One thing to remember is that null is not, conceptually, the same as false or "" or such, e...
How to select a single field for all documents in a MongoDB collection?
... MongoDB, I have a student collection with 10 records having fields name and roll . One record of this collection is:
1...
JavaScript math, round to two decimal places [duplicate]
... ) instead of forcing type coersion as it is more obvious to other people (and you later)
– Hugo Buff
Mar 24 '17 at 14:59
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Why not use java.util.logging?
...
Disclaimer: I am the founder of log4j, SLF4J and logback projects.
There are objective reasons for preferring SLF4J. For one, SLF4J allows the end-user the liberty to choose the underlying logging framework. In addition, savvier users tend to prefer logback which offe...
Android emulator freezing OS X v10.9 (Mavericks) with HAXM
I just updated to OS X v10.9 (Mavericks), and now whenever I start up any of my emulators, as soon as the emulator starts up, my entire computer freezes with a spinning progress indicator in the center of the screen (not a beachball, the progress indicator is similar to what you see when shutting...
Automatically expanding an R factor into a collection of 1/0 indicator variables for every factor le
I have an R data frame containing a factor that I want to "expand" so that for each factor level, there is an associated column in a new data frame, which contains a 1/0 indicator. E.g., suppose I have:
...
What is the difference between currying and partial application?
...rn value is a closure of lambda(z){z(x(y))} with passed-in the values of x and y to f(x,y).
One way to use partial application is to define functions as partial applications of generalized functions, like fold:
function fold(combineFunction, accumulator, list) {/* ... */}
function sum = curry...
Making a Location object in Android with latitude and longitude values
I have a program in which latitude and longitude values of a location are stored in a database, which I download.
3 Answer...
Javascript equivalent of Python's zip function
...0col0","row1col0"],
["row0col1","row1col1"],
["row0col2","row1col2"]]
(and FizzyTea points out that ES6 has variadic argument syntax, so the following function definition will act like python, but see below for disclaimer... this will not be its own inverse so zip(zip(x)) will not equal x; thoug...
How to delete large data of table in SQL without log?
...ty the table, you cannot use WHERE clause to limit the rows being deleted and no triggers will be fired.
On the other hand if you are deleting more than 80-90 Percent of the data, say if you have total of 11 Million rows and you want to delete 10 million another way would be to Insert these 1 mill...