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filter for complete cases in data.frame using dplyr (case-wise deletion)
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187
Try this:
df %>% na.omit
or this:
df %>% filter(complete.cases(.))
or this:
librar...
What is memoization and how can I use it in Python?
... think of it as a cache for method results. For further details, see page 387 for the definition in Introduction To Algorithms (3e), Cormen et al.
A simple example for computing factorials using memoization in Python would be something like this:
factorial_memo = {}
def factorial(k):
if k <...
How do I assign a port mapping to an existing Docker container?
... get to /var/lib/docker/containers folder: stackoverflow.com/a/41226917/2048266, basically run screen ~/Library/Containers/com.docker.docker/Data/com.docker.driver.amd64-linux/tty Once you get the tty running you can navigate to /var/lib/docker
– nommer
Jul 27 ...
Will iOS launch my app into the background if it was force-quit by the user?
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You can achieve this using the new PushKit framework, introduced in iOS 8. Though PushKit is used for VoIP. So your usage should be for VoIP related otherwise there is risk of app rejection. (See this answer).
UDPDATE1:
The documentation has been clarified for iOS8. The documentation can be r...
Upload file to FTP using C#
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Saeb AminiSaeb Amini
18.3k88 gold badges6363 silver badges6565 bronze badges
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Check if a value exists in ArrayList
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Tim Bender
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answered Dec 9 '10 at 23:19
GreenMattGreenMatt...
Vertically align text within a div [duplicate]
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683
Andres Ilich has it right. Just in case someone misses his comment...
A.) If you only have one...
create a trusted self-signed SSL cert for localhost (for use with Express/Node)
...the following command :
openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout cert.key -out cert.pem -config req.cnf -sha256
Step 4. then outside of security folder, in your express app do something like this: (credit goes to @Diego Mello)
backend
/security
/server.js
server.js:
const...
How to execute a Python script from the Django shell?
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edited Jun 22 '17 at 8:00
Jonathan
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answered...