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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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Converting string from snake_case to CamelCase in Ruby
...equire "active_support/core_ext/string" is suffice, providing Rails is installed already.
– Masa Sakano
Jun 23 '18 at 2:03
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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...
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...
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...
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
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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 ...
Select unique or distinct values from a list in UNIX shell script
...n the following input:
class
jar
jar
jar
bin
bin
java
uniq will output all lines exactly once:
class
jar
bin
java
uniq -d will output all lines that appear more than once, and it will print them once:
jar
bin
uniq -u will output all lines that appear exactly once, and it will print them ...
Python: split a list based on a condition?
What's the best way, both aesthetically and from a performance perspective, to split a list of items into multiple lists based on a conditional? The equivalent of:
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