大约有 45,000 项符合查询结果（耗时：0.0405秒） [XML]
Python's equivalent of && (logical-and) in an if-statement
...
1529
You would want and instead of &&.
...
How to get hex color value rather than RGB value?
...
142
var hexDigits = new Array
("0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","...
How to sort a dataframe by multiple column(s)
...ple(order) code:
R> dd[with(dd, order(-z, b)), ]
b x y z
4 Low C 9 2
2 Med D 3 1
1 Hi A 8 1
3 Hi A 9 1
Edit some 2+ years later: It was just asked how to do this by column index. The answer is to simply pass the desired sorting column(s) to the order() function:
R> dd[order(-dd[,4],...
undefined method `source_index' for Gem:Module (NoMethodError)
I'm running a Rails 2.3.5 application and upon running script/server I am shown the following:
5 Answers
...
How do I fit an image (img) inside a div and keep the aspect ratio?
...
12 Answers
12
Active
...
Select random row from a sqlite table
...
216
Have a look at Selecting a Random Row from an SQLite Table
SELECT * FROM table ORDER BY RANDO...
“Missing compiler required member” error being thrown multiple times with almost no changes to code
...
12 Answers
12
Active
...
Concatenating two lists - difference between '+=' and extend()
...
225
The only difference on a bytecode level is that the .extend way involves a function call, whic...
Why isn't sizeof for a struct equal to the sum of sizeof of each member?
...
12 Answers
12
Active
...