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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...
postgresql return 0 if returned value is null
...ns the first of its arguments that is not null.
Null is returned only if all arguments are null. It is often
used to substitute a default value for null values when data is
retrieved for display.
Edit
Here's an example of COALESCE with your query:
SELECT AVG( price )
FROM(
SELECT *, cum...
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...
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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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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Google Chrome form autofill and its yellow background
...mages behind your input field just fill the whole area with white. I tried all the solutions on this page, including the jquery based ones and they didnt work for me, in the end i had to add autocomplete="off" to the field.
– Myke Black
Mar 28 '14 at 15:05
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href=“tel:” and mobile numbers
...ou often find that the first digit of a telephone number is dropped when dialling internationally, even when using international prefixing to dial within the same country.
So as per the trunk prefix for Germany drop the 0 and add the +49 for Germany's international calling code (for example) giving...
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 ...