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Why can't R's ifelse statements return vectors?
...s, you will get longer results:
> ifelse(c(TRUE, FALSE), c(1, 2), c(3, 4))
[1] 1 4
So ifelse is intended for the specific purpose of testing a vector of booleans and returning a vector of the same length, filled with elements taken from the (vector) yes and no arguments.
It is a common confus...
Run a single Maven plugin execution?
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answered Feb 28 '15 at 5:24
JoeJoe
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JavaScript exponents
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47
There is an exponentiation operator, which is part of the ES7 final specification. It is suppos...
Extract substring using regexp in plain bash
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4 Answers
4
Active
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How to pass arguments and redirect stdin from a file to program run in gdb?
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moinudinmoinudin
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What does (function($) {})(jQuery); mean?
...uted in place. Let's break it down a little.
1. (
2. function(){}
3. )
4. ()
Line 2 is a plain function, wrapped in parenthesis to tell the runtime to return the function to the parent scope, once it's returned the function is executed using line 4, maybe reading through these steps will help
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python numpy ValueError: operands could not be broadcast together with shapes
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94
dot is matrix multiplication, but * does something else.
We have two arrays:
X, shape (97,2)
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Convert timedelta to total seconds
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401
Use timedelta.total_seconds().
>>> import datetime
>>> datetime.timedelta(s...
C++11 range based loop: get item by value or reference to const
...ng some examples of range based loops they suggest two main ways 1, 2, 3, 4
4 Answers
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Add EBS to Ubuntu EC2 Instance
... (Ubuntu's internal name for this particular device number):
sudo mkfs.ext4 /dev/xvdf
Only format the file system if this is a new volume with no data on it. Formatting will make it difficult or impossible to retrieve any data that was on this volume previously.
Mount file system (with update to ...