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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 ?
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What is the equivalent of “none” in django templates?
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None, False and True all are available within template tags and filters. None, False, the empty string ('', "", """""") and empty lists/tuples all evaluate to False when evaluated by if, so you can easily do
{% if profile.user.first_name == None...
How to know when UITableView did scroll to bottom in iPhone
...st way is to test a point at the bottom of the screen and use this method call when ever the user scrolls (scrollViewDidScroll):
- (NSIndexPath *)indexPathForRowAtPoint:(CGPoint)point
Test a point near the bottom of the screen, and then using the indexPath it returns check if that indexPath is th...
Preventing Laravel adding multiple records to a pivot table
...ems()->where('foreign_key', $foreignKey)->count() Which, well, actually performs an additional query too '^^ But I don't need to fetch and hydrate the whole collection unless I really need it.
– Silence
May 24 '15 at 13:57
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How to align checkboxes and their labels consistently cross-browsers
...lems that plagues me constantly. How do folks around Stack Overflow vertically align checkboxes and their labels consistently cross-browser ? Whenever I align them correctly in Safari (usually using vertical-align: baseline on the input ), they're completely off in Firefox and IE. Fix it ...
How to implement the factory method pattern in C++ correctly
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First of all, there are cases when
object construction is a task complex
enough to justify its extraction to
another class.
I believe this point is incorrect. The complexity doesn't really matter. The relevance is what does. I...
Is git good with binary files?
...aningful diffs, or merge binary files in any way that could make sense. So all merges, rebases or cherrypicks involving a change to a binary file will involve you making a manual conflict resolution on that binary file.
You need to decide whether the binary file changes are rare enough that you can...
HTML5 Number Input - Always show 2 decimal places
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You can't really, but you a halfway step might be:
<input type='number' step='0.01' value='0.00' placeholder='0.00' />
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What is the difference between JDK and JRE?
...ke javadoc and jdb). It is capable of creating and compiling programs.
Usually, if you only care about running Java programs on computer you will only install the JRE. It's all you need. On the other hand, if you are planning to do some Java programming, you need to install the JDK instead.
Somet...
WebSockets vs. Server-Sent events/EventSource
... a limitation to the maximum number of open connections, which can be specially painful when opening various tabs as the limit is per browser and set to a very low number (6). The issue has been marked as "Won't fix" in Chrome and Firefox. This limit is per browser + domain, so that means that you c...