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Replace all 0 values to NA
...idered as null in statistical analysis. What is the fastest way to replace all the 0 value to NULL in R?
8 Answers
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How do you overcome the svn 'out of date' error?
...sions to download or update. It does something to the metadata, which magically fixes it.
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How to fix committing to the wrong Git branch?
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perfect fix, actually had a couple commits so did HEAD^^ and bam all is gravy
– pablo
Jan 27 '12 at 17:58
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iOS application: how to clear notifications?
...etApplicationIconBadgeNumber: 0];
[[UIApplication sharedApplication] cancelAllLocalNotifications];
which never fails to clear all of the app's notifications from Notification Center.
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How can I propagate exceptions between threads?
We have a function which a single thread calls into (we name this the main thread). Within the body of the function we spawn multiple worker threads to do CPU intensive work, wait for all threads to finish, then return the result on the main thread.
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What is the main difference between Inheritance and Polymorphism?
...class, then you have a Student class that extends Person, Student inherits all the things that Person has. There are some details around the access modifiers you put on the fields/methods in Person, but that's the basic idea. For example, if you have a private field on Person, Student won't see it...
Thread pooling in C++11
... code, that would violate my job integrity.
Edit: to terminate the pool, call the shutdown() method:
XXXX::shutdown(){
{
unique_lock<mutex> lock(threadpool_mutex);
terminate_pool = true;} // use this flag in condition.wait
condition.notify_all(); // wake up all threads.
// ...
Changing all files' extensions in a folder with one command on Windows
...ropriate extensions. It will change from XXX to YYY. If you want to change all extensions, just use the wildcard again:
ren *.* *.YYY
One way to make this work recursively is with the FOR command. It can be used with the /R option to recursively apply a command to matching files. For example:
fo...
Search all of Git history for a string? [duplicate]
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Git can search diffs with the -S option (it's called pickaxe in the docs)
git log -S password
This will find any commit that added or removed the string password. Here a few options:
-p: will show the diffs. If you provide a file (-p file), it will generate a patch for ...
How to join (merge) data frames (inner, outer, left, right)
...nner join: merge(df1, df2) will work for these examples because R automatically joins the frames by common variable names, but you would most likely want to specify merge(df1, df2, by = "CustomerId") to make sure that you were matching on only the fields you desired. You can also use the by.x and b...