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Omit rows containing specific column of NA
... up:
DF[complete.cases(DF), ]
# x y z
# 2 2 10 33
Or if completeFun is already ingrained in your workflow ;)
completeFun(DF, names(DF))
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Accurate way to measure execution times of php scripts
I want to know how many milliseconds a PHP for-loop takes to execute.
14 Answers
14
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How to find all combinations of coins when given some dollar value
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I looked into this once a long time ago, and you can read my little write-up on it. Here’s the Mathematica source.
By using generating functions, you can get a closed-form constant-time solution to the problem. Graham, Knuth, and Patashni...
What is the difference between “Include Directories” and “Additional Include Directories”
...configuration properties of my project, under the "VC++ directories" there is an entry for "Include Directories". But under "C/C++" option, there is another entry called "Additional Include Directories". Same thing happens with library directories.
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What is the difference between Unidirectional and Bidirectional JPA and Hibernate associations?
What is the difference between Unidirectional and Bidirectional associations?
4 Answers
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Passing an array by reference
...er, you can pass any size array to them.
void foo(int (&x)[100]);
This only accepts arrays of 100 integers. You can safely use sizeof on x
void foo(int & x[100]); // error
This is parsed as an "array of references" - which isn't legal.
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Change priorityQueue to max priorityqueue
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How about like this:
PriorityQueue<Integer> queue = new PriorityQueue<>(10, Collections.reverseOrder());
queue.offer(1);
queue.offer(2);
queue.offer(3);
//...
Integer val = null;
while( (val = queue.poll()) != null) {
System...
Batch file to copy files from one folder to another folder
... which all users will store their active data on a server. Now that server is going to be replaced by a new one due to place problem so I need to copy sub folders files from the old server storage folder to new server storage folder. I have below ex:
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Git Pull While Ignoring Local Changes?
Is there a way to do a git pull that ignores any local file changes without blowing the directory away and having to perform a git clone ?
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Clear Application's Data Programmatically
...he hacky way you can also hide the button on the UI, so that functionality is just not available on old phones.
Knowledge of this method is mandatory for anyone using android:manageSpaceActivity.
Whenever I use this, I do so from a manageSpaceActivity which has android:process=":manager". There,...