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How to drop rows of Pandas DataFrame whose value in a certain column is NaN
...ta, including dropna(), is built into pandas explicitly. Aside from potentially improved performance over doing it manually, these functions also come with a variety of options which may be useful.
In [24]: df = pd.DataFrame(np.random.randn(10,3))
In [25]: df.iloc[::2,0] = np.nan; df.iloc[::4,1] ...
How to iterate over arguments in a Bash script
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Use "$@" to represent all the arguments:
for var in "$@"
do
echo "$var"
done
This will iterate over each argument and print it out on a separate line. $@ behaves like $* except that when quoted the arguments are broken up properly if there...
Android: How to enable/disable option menu item on button click?
...
Anyway, the documentation covers all the things.
Changing menu items at runtime
Once the activity is created, the
onCreateOptionsMenu() method is called
only once, as described above. The
system keeps and re-uses the Menu you
define in this meth...
Mysql adding user for remote access
...eated the user in both localhost and '%' wildcard and grant permissions on all DB's as such . See below:
my.cnf (my.ini on windows)
#Replace xxx with your IP Address
bind-address = xxx.xxx.xxx.xxx
then
CREATE USER 'myuser'@'localhost' IDENTIFIED BY 'mypass';
CREATE USER 'myuser'@'%' IDE...
Adding VirtualHost fails: Access Forbidden Error 403 (XAMPP) (Windows 7)
I've got a XAMPP installation running on Windows 7.
9 Answers
9
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Rails 3: I want to list all paths defined in my rails application
I want to list all defined helper path functions (that are created from routes) in my rails 3 application, if that is possible.
...
Deleting all records in a database table
How do I delete all records in one of my database tables in a Ruby on Rails app?
7 Answers
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With GitHub how do I push all branches when adding an existing repo?
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Note: git push --all won't push your tags, only your branches.
git push --all
git push --tags
would really push everything. See also "Set up git to pull and push all branches".
Don't forget the --dry-run option to make some test before act...
Get exit code of a background process
I have a command CMD called from my main bourne shell script that takes forever.
12 Answers
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Why should I prefer single 'await Task.WhenAll' over multiple awaits?
...n case I do not care about the order of task completion and just need them all to complete, should I still use await Task.WhenAll instead of multiple await ? e.g, is DoWork2 below a preferred method to DoWork1 (and why?):
...