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How to rename a single column in a data.frame?
...r.name'
This code pretty much does the following:
names(df) looks into all the names in the df
[names(df) == old.var.name] extracts the variable name you want to check
<- 'new.var.name' assigns the new variable name.
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How to install Xcode Command Line Tools
How do I get the command-line build tools installed with the current Xcode/Mac OS X v10.8 (Mountain Lion) or later?
13 Answ...
How to read last commit comment?
...
Generally:
git log -n
will show you the last n commit messages
More elegantly - if you want a quick overview of your commits
git log --oneline -n
This will Show just the first line of the last n commit messages.
You can sa...
How can I get a list of all functions stored in the database of a particular schema in PostgreSQL?
I want to be able to connect to a PostgreSQL database and find all of the functions for a particular schema.
9 Answers
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How to 'bulk update' with Django?
...ings like incrementing rows:
from django.db.models import F
Entry.objects.all().update(n_pingbacks=F('n_pingbacks') + 1)
See the documentation.
However, note that:
This won't use ModelClass.save method (so if you have some logic inside it won't be triggered).
No django signals will be emitte...
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...
Concurrent.futures vs Multiprocessing in Python 3
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I wouldn't call concurrent.futures more "advanced" - it's a simpler interface that works very much the same regardless of whether you use multiple threads or multiple processes as the underlying parallelization gimmick.
So, like virtuall...
Download file from an ASP.NET Web API method using AngularJS
...he requested file simply by using the code below, and this is supported in all browsers, and will obviously trigger the WebApi request just the same.
$scope.downloadFile = function(downloadPath) {
window.open(downloadPath, '_blank', '');
}
Ajax binary download method:
Using ajax to downlo...
Reintegrate can only be used if revisions X through Y were previously merged from to reintegra
Been using SVN branches with Tortoise 1.6. I've been periodically merging the trunk into the branch to keep it up to date.
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Plotting time in Python with Matplotlib
...erstand why this is the 5th question I've encountered where no one has actually TRIED using a scatter plot - it doesn't work. Type Error - invalid type promotion.
– dwanderson
Oct 5 '16 at 16:21
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