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How do I replace NA values with zeros in an R dataframe?
...then assign it to the location/name on the left. In this case, we aren't really "doing" anything - just making zeroes. The left side is saying: look at the d object, inside the d object (the square brackets), find all the elements that return TRUE (is.na(d) returns a logical for each element). Once...
Check if object value exists within a Javascript array of objects and if not add a new object to arr
...his is what I did in addition to @sagar-gavhane's answer
const newUser = {_id: 4, name: 'Adam'}
const users = [{_id: 1, name: 'Fred'}, {_id: 2, name: 'Ted'}, {_id: 3, 'Bill'}]
const userExists = users.some(user => user.name = newUser.name);
if(userExists) {
return new Error({error:'User exi...
How to get the current time in milliseconds from C in Linux?
...
This can be achieved using the POSIX clock_gettime function.
In the current version of POSIX, gettimeofday is marked obsolete. This means it may be removed from a future version of the specification. Application writers are encouraged to use the clock_gettime functi...
Biggest GWT Pitfalls? [closed]
...that we chose to implement using GWT. Has anyone encountered any major pitfalls in using GWT (and GWT-EXT) that were unable to be overcome? How about from a performance perspective?
...
How do you run a crontab in Cygwin on Windows?
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You need to also install cygrunsrv so you can set cron up as a windows service, then run cron-config.
If you want the cron jobs to send email of any output you'll also need to install either exim or ssmtp (before running cron-config.)
See /usr/...
How can I convert an RGB image into grayscale in Python?
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SciPy's image I/O is literally PIL/Pillow. Hence, testing SciPy is effectively retesting PIL/Pillow with negligible overhead introduced by SciPy's wrapper functions. It would have been much more useful to substitute OpenCV (which does not leverage PIL...
How should I handle “No internet connection” with Retrofit on Android
...an> isNetworkActive) {
isNetworkActive.subscribe(
_isNetworkActive -> this.isNetworkActive = _isNetworkActive,
_error -> Log.e("NetworkActive error " + _error.getMessage()));
}
@Override
public Response intercept(Interceptor.Chain chain) thr...
Join/Where with LINQ and Lambda
...re post.ID == id
select new { Post = post, Meta = meta };
If you're really stuck on using lambdas though, your syntax is quite a bit off. Here's the same query, using the LINQ extension methods:
var id = 1;
var query = database.Posts // your starting point - table in the "from" statement
...
How do I allow HTTPS for Apache on localhost?
... up HTTPS with a self-signed cert on Apache on localhost, but how do I actually do that? I have no idea at all.
16 Answers
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Multiline bash commands in makefile
...colon:
foo:
for i in `find`; \
do \
all="$$all $$i"; \
done; \
gcc $$all
But if you just want to take the whole list returned by the find invocation and pass it to gcc, you actually don't necessarily need a multiline command:
foo:
...