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Apply multiple functions to multiple groupby columns
...tom function that returns a Series of all the aggregations. Use the Series index as labels for the new columns:
def f(x):
d = {}
d['a_sum'] = x['a'].sum()
d['a_max'] = x['a'].max()
d['b_mean'] = x['b'].mean()
d['c_d_prodsum'] = (x['c'] * x['d']).sum()
return pd.Series(d, ind...
What's the Best Way to Shuffle an NSMutableArray?
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You don't need the swapObjectAtIndex method. exchangeObjectAtIndex:withObjectAtIndex: already exists.
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Can I set an opacity only to the background image of a div?
...t;
Hi there
</div>
CSS
.myDiv {
position: relative;
z-index: 1;
}
.myDiv .bg {
position: absolute;
z-index: -1;
top: 0;
bottom: 0;
left: 0;
right: 0;
background: url(test.jpg) center center;
opacity: .4;
width: 100%;
height: 100%;
}
See...
Fatal Error: Allowed Memory Size of 134217728 Bytes Exhausted (CodeIgniter + XML-RPC)
I have a bunch of client point of sale (POS) systems that periodically send new sales data to one centralized database, which stores the data into one big database for report generation.
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How do I create a PDO parameterized query with a LIKE statement?
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PDO should be escaping that % in the execute call. Kaqai's answer is better
– Peter Bagnall
Nov 13 '16 at 14:52
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Creating default object from empty value in PHP?
... on this. BTW, this exchange has led me to realize that italics<bold<allcaps in terms of "strength" and that while allcaps=shouting and italics=politeEmphasis, bold is in a middle ground where the acceptability is questionable. :-)
– Peter Alfvin
Nov 23 '...
How to get a time zone from a location using latitude and longitude coordinates?
... zone from a location. This community wiki is an attempt at consolidating all of the valid responses.
17 Answers
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In PHP, what is a closure and why does it use the “use” identifier?
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This is how PHP expresses a closure. This is not evil at all and in fact it is quite powerful and useful.
Basically what this means is that you are allowing the anonymous function to "capture" local variables (in this case, $tax and a reference to $total) outside of it scope and...
Why do assignment statements return a value?
...in the answers of this thread. But efficient in the case of properties and indexers that use get- and set accessors? Not at all. Consider this code:
class Test
{
public bool MyProperty { get { return true; } set { ; } }
}
Here we have a property, which isn't even a wrapper for a private varia...
How can I write to the console in PHP?
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Firefox
On Firefox you can use an extension called FirePHP which enables the logging and dumping of information from your PHP applications to the console. This is an addon to the awesome web development extension Firebug.
http://www.studytrails.com/blog/using-firephp-...