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How to store a command in a variable in a shell script?
I would like to store a command to use at a later period in a variable (not the output of the command, but the command itself)
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How can I remove a specific item from an array?
...ethod changes the contents of an array by removing
existing elements and/or adding new elements.
const array = [2, 5, 9];
console.log(array);
const index = array.indexOf(5);
if (index > -1) {
array.splice(index, 1);
}
// array = [2, 9]
console.log(array);
The second...
Where can I learn how to write C code to speed up slow R functions? [closed]
What's the best resource for learning how to write C code for use with R? I know about the system and foreign language interfaces section of R extensions, but I find it pretty hard going. What are good resources (both online and offline) for writing C code for use with R?
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How does a Breadth-First Search work when looking for Shortest Path?
...'ve done some research, and I seem to be missing one small part of this algorithm. I understand how a Breadth-First Search works, but I don't understand how exactly it will get me to a specific path, as opposed to just telling me where each individual node can go. I guess the easiest way to explain ...
What is the most frequent concurrency issue you've encountered in Java? [closed]
This is a poll of sorts about common concurrency problems in Java. An example might be the classic deadlock or race condition or perhaps EDT threading bugs in Swing. I'm interested both in a breadth of possible issues but also in what issues are most common. So, please leave one specific answer o...
In Java, what does NaN mean?
...
Taken from this page:
"NaN" stands for "not a number". "Nan"
is produced if a floating point
operation has some input parameters
that cause the operation to produce
some undefined result. For example,
0.0 divided by 0.0 is arithmetically undefined. Ta...
How do I move files in node.js?
...can I move files (like mv command shell) on node.js? Is there any method for that or should I read a file, write to a new file and remove older file?
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vector::at vs. vector::operator[]
...ndary checking, which is also discussed in similar questions like C++ Vector at/[] operator speed or ::std::vector::at() vs operator[] << surprising results!! 5 to 10 times slower/faster! . I just don't understand what the at() method is good for.
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Ruby: Change negative number to positive number?
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my answer is just for negative numbers, if you need to always have the absolute value then this is definitely the better way.
– Brandon Bodnar
Mar 19 '10 at 22:41
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Casting to string in JavaScript
...und three ways to cast a variable to String in JavaScript.
I searched for those three options in the jQuery source code, and they are all in use .
I would like to know if there are any differences between them:
...