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Pandas aggregate count distinct
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How about either of:
>>> df
date duration user_id
0 2013-04-01 30 0001
1 2013-04-01 15 0001
2 2013-04-01 20 0002
3 2013-04-02 15 0002
4 2013-04-02 30 0002
>>> df.groupby("date").agg({"duration": np.sum, "use...
Find and Replace text in the entire table using a MySQL query
Usually I use manual find to replace text in a MySQL database using phpmyadmin. I'm tired of it now, how can I run a query to find and replace a text with new text in the entire table in phpmyadmin?
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How to specify the default error page in web.xml?
... 2.5, there's no other way than specifying every common HTTP error individually. You need to figure which HTTP errors the enduser could possibly face. On a barebones webapp with for example the usage of HTTP authentication, having a disabled directory listing, using custom servlets and code which ca...
Add up a column of numbers at the Unix shell
... . . .| x=$(echo <(cat)); echo $((0+${x// /+}+0)) if you want all bash all the time:
– qneill
Apr 3 '15 at 23:31
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Best way to specify whitespace in a String.Split operation
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If you just call:
string[] ssize = myStr.Split(null); //Or myStr.Split()
or:
string[] ssize = myStr.Split(new char[0]);
then white-space is assumed to be the splitting character. From the string.Split(char[]) method's documentation page...
AngularJS: Is there any way to determine which fields are making a form invalid?
...lowing code in an AngularJS application, inside of a controller,
which is called from an ng-submit function, which belongs to a form with name profileForm :
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Max parallel http connections in a browser?
...server (comet, reverse ajax, etc). It works ok, but I see the browser only allows two suspended connections to a given domain simultaneously. So if a user is looking at my website in Tab1 of their browser, then also tries loading it in Tab2, they've used up the two allowed connections to my site.
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Android Camera : data intent returns null
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Really helpful answer I wish I could accept it for others to find the solution more efficiently.
– user1160020
May 3 '13 at 13:32
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CSS Box Shadow Bottom Only [duplicate]
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Do this:
box-shadow: 0 4px 2px -2px gray;
It's actually much simpler, whatever you set the blur to (3rd value), set the spread (4th value) to the negative of it.
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impr...
std::shared_ptr thread safety explained
...ly regarding your original 3 questions.
But the ending part of your edit
Calling reset() in thread IV will delete previous instance of A class created in first thread and replace it with new instance? Moreover after calling reset() in IV thread other threads will see only newly created object?
is ...