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Checking if output of a command contains a certain string in a shell script
...p;> /dev/null
if [ $? == 0 ]; then
echo "matched"
fi
which is done idiomatically like so:
if ./somecommand | grep -q 'string'; then
echo "matched"
fi
and also:
./somecommand | grep -q 'string' && echo 'matched'
...
Creating a new column based on if-elif-else condition
...
To formalize some of the approaches laid out above:
Create a function that operates on the rows of your dataframe like so:
def f(row):
if row['A'] == row['B']:
val = 0
elif row['A'] > row['B']:
val = 1
else:
val = -1
r...
How to open a file using the open with statement
...answered Feb 14 '12 at 19:28
David HeffernanDavid Heffernan
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How do I call Objective-C code from Swift?
...m
Add a .m file to your class, and name it CustomObject.m.
Step 2: Add Bridging Header
When adding your .m file, you'll likely be hit with a prompt that looks like this:
Click Yes!
If you did not see the prompt, or accidentally deleted your bridging header, add a new .h file to your project...
Rails migrations: self.up and self.down versus change
... rollback? It's not possible, so you need to define the down method.
As said, I suggest you to read the Rails Migrations Guide.
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Nginx not picking up site in sites-enabled?
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I had the same problem. It was because I had accidentally used a relative path with the symbolic link.
Are you sure you used full paths, e.g.:
ln -s /etc/nginx/sites-available/example.com.conf /etc/nginx/sites-enabled/example.com.conf
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Is it possible for intellij to organize imports the same way as in Eclipse?
...on a project where all the team members are using Eclipse and I'm the only IDEA user. This creates a lot of noise from imports rearrangements. The order in which eclipse imports is: Java, Javax, Org, Com, everything else in alphabetical order. Is it possible to configure IDEA to follow these rules?
...
What is `params.require(:person).permit(:name, :age)` doing in Rails 4?
..., but it's actually an instance of ActionController::Parameters, which provides several methods such as require and permit.
The require method ensures that a specific parameter is present, and if it's not provided, the require method throws an error. It returns an instance of ActionController::Par...
How to Customize the time format for Python logging?
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That said, the OP doesn't want msecs to appear at all!
– Oddthinking
Nov 1 '16 at 11:23
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Can I simultaneously declare and assign a variable in VBA?
...
You can sort-of do that with objects, as in the following.
Dim w As New Widget
But not with strings or variants.
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