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How to reshape data from long to wide format
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The reshape comments and similar argument names aren't all that helpful. However, I have found that for long to wide, you need to provide data = your data.frame, idvar = the variable that identifies your groups, v.names = the variables that will become multiple columns in wide f...
How do I find which program is using port 80 in Windows? [duplicate]
... Then you either need to watch through list carefully or install some additional software. technet.microsoft.com/en-us/sysinternals/bb897437.aspx for example.
– n0rd
Dec 25 '09 at 8:14
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How do I get only directories using Get-ChildItem?
I'm using PowerShell 2.0 and I want to pipe out all the subdirectories of a certain path. The following command outputs all files and directories, but I can't figure out how to filter out the files.
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Web-scraping JavaScript page with Python
...a web driver fast enough and easy to get the work done.
Once you have installed Phantom JS, make sure the phantomjs binary is available in the current path:
phantomjs --version
# result:
2.1.1
Example
To give an example, I created a sample page with following HTML code. (link):
<!DOCTYPE ht...
Best practices for in-app database migration for Sqlite
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I maintain an application that periodically needs to update a sqlite database and migrate old databases to the new schema and here's what I do:
For tracking the database version, I use the built in user-version variable that sqlite provides (sqlite does nothing w...
Integrating MySQL with Python in Windows
...rrently, I would recommend using PyMySQL. It's pure python, so it supports all OSes equally, it's almost a drop-in replacement for mysqldb, and it also works with python 3. The best way to install it is using pip. You can install it from here (more instructions here), and then run:
pip install pymy...
Django-Admin: CharField as TextArea
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Starting from Django 1.7 you need to add also fields = '__all__' under class Meta:.
– skoll
May 4 '16 at 11:43
2
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Targeting .NET Framework 4.5 via Visual Studio 2010
Today I installed the .NET Framework 4.5 on my machine expecting to be able to use it from Visual Studio 2010, since it's just a minor update that should't pose problems for Visual Studio 2010. Unfortunately I am not, even manually removing certain 4.0 and adding the corresponding 4.5 assemblies r...
pass post data with window.location.href
...n attribute of the form to the URL and the method attribute to POST, then call the submit method on the form tag.
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Why is iterating through a large Django QuerySet consuming massive amounts of memory?
...rst time you iterate over it. For example, this will print the headline of all entries in the database:
for e in Entry.objects.all():
print e.headline
So your ten million rows are retrieved, all at once, when you first enter that loop and get the iterating form of the queryset. The wait ...