大约有 46,000 项符合查询结果（耗时：0.0302秒） [XML]
How to grant remote access to MySQL for a whole subnet?
... |
edited Nov 14 '17 at 20:33
answered Jul 31 '12 at 15:01
...
How do I base64 encode (decode) in C?
...
106
Here's the one I'm using:
#include <stdint.h>
#include <stdlib.h>
static char en...
Why do Lua arrays(tables) start at 1 instead of 0?
...
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.
...
Add a common Legend for combined ggplots
...
108
Update 2015-Feb
See Steven's answer below
df1 <- read.table(text="group x y
gro...
Sample random rows in dataframe
...
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, ...
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...
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.
...
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...
How do I make an html link look like a button?
...
answered Apr 2 '09 at 15:06
TStamperTStamper
28.2k1010 gold badges6161 silver badges7272 bronze badges
...