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When is std::weak_ptr useful?
...want to keep them in memory, so you hold a strong pointer to them. Periodically, you scan the cache and decide which objects have not been accessed recently. You don't need to keep those in memory, so you get rid of the strong pointer.
But what if that object is in use and some other code holds a s...
Apply multiple functions to multiple groupby columns
...ion.
I recommend making a single custom 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...
What is default color for text in textview?
...ion, text color defined by theme is not inherited by TextView added dynamically from code. It always appears in white regardless of dark/light theme.
– shiouming
Dec 20 '17 at 23:54
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How do I setup a SSL certificate for an express.js server?
... cert provider.
– SCBuergel.eth
Aug 10 '16 at 9:52
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show 3 more comments
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Python: What OS am I running on?
...ed just "Linux".
– erb
Jun 9 '17 at 10:22
4
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Can jQuery provide the tag name?
...Name.toLowerCase(), as most DOM representations of HTML documents automatically uppercase the nodeName.
– NickFitz
Oct 7 '09 at 15:27
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Creating an empty Pandas DataFrame, then filling it?
...utocompletion), but that works with strings as date format, right? The overall approach works though (I changed index to something else).
– Matthias Kauer
Dec 15 '12 at 8:42
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How to update Python?
I have version 2.7 installed from early 2012. I can't find any consensus on whether I should completely uninstall and wipe this version before putting on the latest version.
...
how to create a file name with the current date & time in python?
...
LevonLevon
109k2727 gold badges180180 silver badges176176 bronze badges
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What are unit tests, integration tests, smoke tests, and regression tests?
...re we just check that when the system under test is invoked it returns normally and does not blow up.
Smoke testing is both an analogy with electronics, where the first test occurs when powering up a circuit (if it smokes, it's bad!)...
... and, apparently, with plumbing, where a system of pipes i...