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Using bitwise OR 0 to floor a number
...ator casts the
number to an integer, thus removing the fractional part
All bitwise operations except unsigned right shift, >>>, work on signed 32-bit integers. So using bitwise operations will convert a float to an integer.
Does it have any advantages over doing Math.floor? Maybe it...
What's the difference between lapply and do.call?
I'm learning R recently and confused by two function: lapply and do.call . It seems that they're just similar to map function in Lisp. But why are there two functions with such a different name? Why doesn't R just use a function called map ?
...
Are there constants in JavaScript?
... const:
const MY_CONSTANT = "some-value";
This will work in pretty much all browsers except IE 8, 9 and 10. Some may also need strict mode enabled.
You can use var with conventions like ALL_CAPS to show that certain values should not be modified if you need to support older browsers or are worki...
Datatables: Cannot read property 'mData' of undefined
...o went through this link which didn't yield any results. I have included all the prerequisites where I'm parsing data directly into the DOM. Kindly help me to fix this issue.
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How to populate/instantiate a C# array with a single value?
I know that instantiated arrays of value types in C# are automatically populated with the default value of the type (e.g. false for bool, 0 for int, etc.).
...
jquery sortable placeholder height problem
For some reason the placeholder for my sortable items is about 10px. All my sortable items have different heights. How can I change the height of each placeholder to match the item being moved?
...
Why does Python pep-8 strongly recommend spaces over tabs for indentation?
...andard library in the main Python distribution.
The intention is to make all code that goes in the official python distribution consistently formatted (I hope we can agree that this is universally a Good Thing™).
Since the decision between spaces and tabs for an individual programmer is a) real...
MySQL: multiple tables or one table with many columns?
...elational database to minimize redundancy and dependency. Normalization usually involves dividing large tables into smaller (and less redundant) tables and defining relationships between them. The objective is to isolate data so that additions, deletions, and modifications of a field can be made in ...
What requests do browsers' “F5” and “Ctrl + F5” refreshes generate?
...
Generally speaking:
F5 may give you the same page even if the content is changed, because it may load the page from cache. But Ctrl-F5 forces a cache refresh, and will guarantee that if the content is changed, you will get the ne...
Overriding id on create in ActiveRecord
...why you can't use mass-assignment to set it. However, when setting it manually, it just works:
o = SomeObject.new
o.id = 8888
o.save!
o.reload.id # => 8888
I'm not sure what the original motivation was, but I do this when converting ActiveHash models to ActiveRecord. ActiveHash allows you to...