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Changing a specific column name in pandas DataFrame
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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...
How to remove a field from params[:something]
... = params.except[the one I wish to remove]
This is a safer way to 'grab' all the params you need into a copy WITHOUT destroying the original passed in params (which is NOT a good thing to do as it will make debugging and maintenance of your code very hard over time).
Or you could just pass direc...
How do you use variables in a simple PostgreSQL script?
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This doesn't answer the question at all. In MS SQL you can define a var in a query and use it right there, in the same tool. I don't get why people keep proposing this as an answer, in every version of this question.
– stone
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How to assign from a function which returns more than one value?
...eturningTwoValues()
If you only need the first or second component these all work too:
list[a] <- functionReturningTwoValues()
list[a, ] <- functionReturningTwoValues()
list[, b] <- functionReturningTwoValues()
(Of course, if you only needed one value then functionReturningTwoValues()[...
Windows 7 SDK installation failure
I seem to be completely unable to install the Windows 7 SDK onto my machine, and the only solution I've found on the web is to make a swathe of registry changes. I've done this - still no success.
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How can I reset a react component including all transitively reachable state?
I occasionally have react components that are conceptually stateful which I want to reset. The ideal behavior would be equivalent to removing the old component and readding a new, pristine component.
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How to handle invalid SSL certificates with Apache HttpClient? [duplicate]
...thority, but a self
signed or issued by a private CMS.
Don't panic. All you need to do is to
add the server certificate to your
trusted Java key store if your client
is written in Java. You might be
wondering how as if you can not access
the machine where the server is
installed. ...
Determine if Android app is being used for the first time
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Beware for Android 6.0 (API 23 - Marshmallow) or above auto backup (developer.android.com/guide/topics/data/autobackup.html)is enabled by default. If the users uninstalls and then reinstalls the app the shared preferences will be recovered. So on reinstalls you ca...
Lambda function in list comprehensions
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The first one creates a single lambda function and calls it ten times.
The second one doesn't call the function. It creates 10 different lambda functions. It puts all of those in a list. To make it equivalent to the first you need:
[(lambda x: x*x)(x) for x in range(10)]
Or b...
Using Default Arguments in a Function
...= "some other value";
}
code here!
}
This way, you can make a call like foo('blah', null, 'non-default y value'); and have it work as you want, where the second parameter $x still gets its default value.
With this method, passing a null value means you want the default value for one par...