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How to reorder data.table columns (without copying)
...ta.table(a = 1:3, b = 3:1, c = runif(3))
x
# a b c
# [1,] 1 3 0.2880365
# [2,] 2 2 0.7785115
# [3,] 3 1 0.3297416
setcolorder(x, c("c", "b", "a"))
x
# c b a
# [1,] 0.2880365 3 1
# [2,] 0.7785115 2 2
# [3,] 0.3297416 1 3
From ?setcolorder:
In data.table parlance, all s...
Regular expression for a hexadecimal number?
...
How about the following?
0[xX][0-9a-fA-F]+
Matches expression starting with a 0, following by either a lower or uppercase x, followed by one or more characters in the ranges 0-9, or a-f, or A-F
...
How do I verify that an Android apk is signed with a release certificate?
... |
edited Jan 27 '17 at 20:05
Eugene
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answered Au...
Given an array of numbers, return array of products of all other numbers (no division)
...
260
An explanation of polygenelubricants method is:
The trick is to construct the arrays (in the c...
Where is the WPF Numeric UpDown control?
...
50
Simply use the IntegerUpDown control in the xtended wpf toolkit
You can use it like this:
Add ...
How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
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640
Difference between == and ===
The difference between the loosely == equal operator and the stri...
Python division
I was trying to normalize a set of numbers from -100 to 0 to a range of 10-100 and was having problems only to notice that even with no variables at all, this does not evaluate the way I would expect it to:
...
Path to Powershell.exe (v 2.0)
Where is the Powershell (version 2.0) located? What is the path to Powershell.exe? I have Windows Server 2008 and Powershell installed. When I look at this folder:
...
Expand a random range from 1–5 to 1–7
...2, 3 },
{ 4, 5, 6, 7, 1 },
{ 2, 3, 4, 5, 6 },
{ 7, 0, 0, 0, 0 }
};
int result = 0;
while (result == 0)
{
int i = rand5();
int j = rand5();
result = vals[i-1][j-1];
}
return result;
}
How does it work? Think of it like this: i...
Label points in geom_point
...our="green", label=Name))+
geom_point() +geom_text(aes(label=Name),hjust=0, vjust=0)
EDIT: Label only values above a certain threshold:
ggplot(nba, aes(x= MIN, y= PTS, colour="green", label=Name))+
geom_point() +
geom_text(aes(label=ifelse(PTS>24,as.character(Name),'')),hjust=0,vjust...