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Random row selection in Pandas dataframe
... Thanks @eumiro. I also worked out that df.ix[np.random.random_integers(0, len(df), 10)] would also work.
– John
Apr 10 '13 at 10:58
7
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Changing a specific column name in pandas DataFrame
...
A one liner does exist:
In [27]: df=df.rename(columns = {'two':'new_name'})
In [28]: df
Out[28]:
one three new_name
0 1 a 9
1 2 b 8
2 3 c 7
3 4 d 6
4 5 e 5
Following is the docstring for the rename method.
De...
What does -fPIC mean when building a shared library?
...es and independence between individual modules, but I'm not sure what it really means. Can you explain?
3 Answers
...
Any way to replace characters on Swift String?
...n leaves me with and optional string. Original String looks like this: "x86_64" and the new mapping looks like "Optional([\"x\", \"8\", \"6\", \"_\", \"6\", \"4\"])"
– John Shelley
Oct 19 '15 at 15:07
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SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
...
Without the update-and-join notation (not all DBMS support that), use:
UPDATE QuestionTrackings
SET QuestionID = (SELECT QuestionID
FROM AnswerTrackings
WHERE AnswerTrackings.AnswerID = QuestionTrackings.AnswerID)
...
Rails render partial with block
...
In Rails 5.0 there was a change so this is general to all partials, not just layouts. You can change the first line of the calling code to: <%= render '/shared/panel', title: 'some title' do %>
– Jay Mitchell
Sep 26 '19 at 20:10
...
“Uncaught TypeError: Illegal invocation” in Chrome
...ou are assigning a native method to a property of custom object.
When you call support.animationFrame(function () {}) , it is executed in the context of current object (ie support). For the native requestAnimationFrame function to work properly, it must be executed in the context of window.
So the ...
“Debug certificate expired” error in Eclipse Android plugins
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Upon installation, the Android SDK generates a debug signing certificate for you in a keystore called debug.keystore. The Eclipse plug-in uses this certificate to sign each application build that is generated.
Unfortunately a debug ...
Advantages to Using Private Static Methods
When creating a class that has internal private methods, usually to reduce code duplication, that don't require the use of any instance fields, are there performance or memory advantages to declaring the method as static?
...
Why can templates only be implemented in the header file?
...f;
When reading this line, the compiler will create a new class (let's call it FooInt), which is equivalent to the following:
struct FooInt
{
int bar;
void doSomething(int param) {/* do stuff using int */}
}
Consequently, the compiler needs to have access to the implementation of the m...