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How to grant remote access to MySQL for a whole subnet?
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edited Nov 14 '17 at 20:33
answered Jul 31 '12 at 15:01
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Add a common Legend for combined ggplots
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108
Update 2015-Feb
See Steven's answer below
df1 <- read.table(text="group x y
gro...
How do you round a floating point number in Perl?
... and floor()?
Trig functions?
Remember that int() merely truncates toward 0. For rounding to a certain number of digits, sprintf() or printf() is usually the easiest
route.
printf("%.3f", 3.1415926535); # prints 3.142
The POSIX module (part of the standard Perl distribution) implement...
Delete element in a slice
... arguments to a variadic function.
So what this line does:
a = append(a[:0], a[1:]...)
is essentially:
a = append(a[:0], a[1], a[2])
Now, you may be wondering, why not just do
a = append(a[1:]...)
Well, the function definition of append is
func append(slice []Type, elems ...Type) []Type
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Why do Lua arrays(tables) start at 1 instead of 0?
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Although I too found them weird at the beginning, I have learned to love 0-based arrays. But I get by OK with Lua's 1-based arrays, especially by
using Lua's generic for loop and the ipairs operator—I can usually avoid worrying about just how arrays are indexed.
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Sample random rows in dataframe
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460
First make some data:
> df = data.frame(matrix(rnorm(20), nrow=10))
> df
X1 ...
pandas: filter rows of DataFrame with operator chaining
... boolean index.
In [96]: df
Out[96]:
A B C D
a 1 4 9 1
b 4 5 0 2
c 5 5 1 0
d 1 3 9 6
In [99]: df[(df.A == 1) & (df.D == 6)]
Out[99]:
A B C D
d 1 3 9 6
If you want to chain methods, you can add your own mask method and use that one.
In [90]: def mask(df, key, ...
What's the difference between a single precision and double precision floating point operation?
...entation requires a 32 bit word, which may be represented as numbered from 0 to 31, left to right.
The first bit is the sign bit, S,
the next eight bits are the exponent bits, 'E', and
the final 23 bits are the fraction 'F':
S EEEEEEEE FFFFFFFFFFFFFFFFFFFFFFF
0 1 8 9 3...
Find XOR of all numbers in a given range
...ven a large range [a,b] where 'a' and 'b' can be typically between 1 and 4,000,000,000 inclusive. You have to find out the XOR of all the numbers in the given range.
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plot a circle with pyplot
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205
You need to add it to an axes. A Circle is a subclass of an Artist, and an axes has an add_arti...