大约有 41,200 项符合查询结果（耗时：0.0280秒） [XML]
In Clojure, when should I use a vector over a list, and the other way around?
...: no, but they are sequential
[12:21] <rhickey> ,(sequential? [1 2 3])
[12:21] <clojurebot> true
[12:22] <Raynes> When would you want to use a list over a vector?
[12:22] <rhickey> when generating code, when generating back-to-front
[12:23] <rhickey> not too...
Most efficient way of making an if-elif-elif-else statement when the else is done the most?
...:
the_thing = 2
elif something == 'there':
the_thing = 3
else:
the_thing = 4
2.py
something = 'something'
options = {'this': 1, 'that': 2, 'there': 3}
for i in xrange(1000000):
the_thing = options.get(something, 4)
3.py
something = 'something'
options = {'t...
The 'json' native gem requires installed build tools
I have ruby 1.9.2p180 (2011-02-18) [i386-mingw32] installed on my windows 7 machine. Now I tried to install the JSON gem using the command, "gem install json" and got the following error.
...
not None test in Python [duplicate]
...
1033
if val is not None:
# ...
is the Pythonic idiom for testing that a variable is not set to...
How to escape braces (curly brackets) in a format string in .NET
...
For you to output foo {1, 2, 3} you have to do something like:
string t = "1, 2, 3";
string v = String.Format(" foo {{{0}}}", t);
To output a { you use {{ and to output a } you use }}.
or Now, you can also use c# string interpolation like this (featu...
How to split a string in shell and get the last field
Suppose I have the string 1:2:3:4:5 and I want to get its last field ( 5 in this case). How do I do that using Bash? I tried cut , but I don't know how to specify the last field with -f .
...
Preferred way to create a Scala list
...end is O(1).
– Daniel C. Sobral
Aug 31 '15 at 19:33
@pgoggijr That is not true. First, there's no "change" anywhere, b...
Fast permutation -> number -> permutation mapping algorithms
I have n elements. For the sake of an example, let's say, 7 elements, 1234567. I know there are 7! = 5040 permutations possible of these 7 elements.
...
Getting a map() to return a list in Python 3.x
...
Do this:
list(map(chr,[66,53,0,94]))
In Python 3+, many processes that iterate over iterables return iterators themselves. In most cases, this ends up saving memory, and should make things go faster.
If all you're going to do is iterate over thi...
How to extract a floating number from a string [duplicate]
I have a number of strings similar to Current Level: 13.4 db. and I would like to extract just the floating point number. I say floating and not decimal as it's sometimes whole. Can RegEx do this or is there a better way?
...