大约有 43,100 项符合查询结果（耗时：0.0604秒） [XML]
For each row in an R dataframe
...
105
You can try this, using apply() function
> d
name plate value1 value2
1 A P1 ...
[ :Unexpected operator in shell programming [duplicate]
...
answered Aug 5 '10 at 1:08
WolphWolph
66.6k99 gold badges120120 silver badges141141 bronze badges
...
What is “android.R.layout.simple_list_item_1”?
...
|
edited Jul 3 '13 at 3:21
Aaron Klap
24322 silver badges99 bronze badges
answered Sep 8 '10 a...
What does %~d0 mean in a Windows batch file?
...arguments used to invoke the file: %0 is the path to the bat-file itself, %1 is the first argument after, %2 is the second and so on.
Since the arguments are often file paths, there is some additional syntax to extract parts of the path. ~d is drive, ~p is the path (without drive), ~n is the file n...
Split comma-separated strings in a column into separate rows
...
81
This old question frequently is being used as dupe target (tagged with r-faq). As of today, it h...
How to delete from select in MySQL?
...
210
SELECT (sub)queries return result sets. So you need to use IN, not = in your WHERE clause.
Add...
Formatting Numbers by padding with leading zeros in SQL Server
We have an old SQL table that was used by SQL Server 2000 for close to 10 years.
13 Answers
...
C Macro definition to determine big endian or little endian machine?
...
19 Answers
19
Active
...
Which characters need to be escaped when using Bash?
...
291
There are two easy and safe rules which work not only in sh but also bash.
1. Put the whole str...
What is the best Battleship AI?
... games per match. Doing 50 games is just flipping a coin. I needed to do 1000 games to get any reasonable distinction between test algorithms.
Download Dreadnought 1.2.
Strategies:
keep track of all possible positions for ships that have >0 hits. The list never gets bigger than ~30K so it ...