大约有 48,000 项符合查询结果（耗时：0.0337秒） [XML]
Automatically expanding an R factor into a collection of 1/0 indicator variables for every factor le
I have an R data frame containing a factor that I want to "expand" so that for each factor level, there is an associated column in a new data frame, which contains a 1/0 indicator. E.g., suppose I have:
...
Limit file format when using ?
...I'd like to know if there is a solution. I'd like to keep solely to HTML and JavaScript; no Flash please.
11 Answers
...
How to iterate through two lists in parallel?
I have two iterables in Python, and I want to go over them in pairs:
8 Answers
8
...
Disable browser's back button
...
Do not disable expected browser behaviour.
Make your pages handle the possibility of users going back a page or two; don't try to cripple their software.
share
|
improve this answer
...
Which terminal command to get just IP address and nothing else?
...
It says that -i and -I are both illegal options
– Mason
Dec 16 '11 at 3:08
3
...
Is it possible to use jQuery .on and hover?
...after the initial page load. I'm currently using .bind with mouseover and mouseout .
10 Answers
...
Difference between VARCHAR and TEXT in MySQL [duplicate]
....
VARCHAR(M)
variable max size of M characters
M needs to be between 1 and 65535
takes 1 + c bytes (for M ≤ 255) or 2 + c (for 256 ≤ M ≤ 65535) bytes of disk space where c is the length of the stored string
can be part of an index
More Details
TEXT has a fixed max size of 2¹⁶-1 = 655...
What's the simplest way to test whether a number is a power of 2 in C++?
...will want to check for it explicitly.
http://www.graphics.stanford.edu/~seander/bithacks.html has a large collection of clever bit-twiddling algorithms, including this one.
share
|
improve this ans...
How to compare two floating point numbers in Bash?
...) )); then
…
fi
Explanation
Piping through the basic calculator command bc returns either 1 or 0.
The option -l is equivalent to --mathlib; it loads the standard math library.
Enclosing the whole expression between double parenthesis (( )) will translate these values to respectively true or...
How to select the first element with a specific attribute using XPath
...n 17 '09 at 10:48
Jonathan FinglandJonathan Fingland
52k1111 gold badges7979 silver badges7777 bronze badges
...