大约有 46,000 项符合查询结果（耗时：0.0581秒） [XML]
Remove duplicated rows using dplyr
...rame [3 x 3]
## Groups: x, y
##
## x y z
## 1 0 1 1
## 2 1 0 2
## 3 1 1 4
(In dplyr 0.2 you won't need the dummy z variable and will just be
able to write row_number() == 1)
I've also been thinking about adding a slice() function that would
work like:
df %>% group_by(x, y) %>% slice(fro...
RedirectToAction between areas?
...
answered Sep 8 '09 at 5:41
eu-ge-neeu-ge-ne
27k66 gold badges6868 silver badges6262 bronze badges
...
Some questions about Automatic Reference Counting in iOS5 SDK
I'm currently developing an app for iPad. The development started for iOS 4.2 and is now continuing (and I think will be completed) for iOS 4.3.
I just read about ARC in iOS 5, and basically I understood that we will never need to release and retain objects anymore. My questions are:
...
Razor doesn't understand unclosed html tags
...
4 Answers
4
Active
...
How to sort a list in Scala by two fields?
...
4 Answers
4
Active
...
Node.js - Find home directory in platform agnostic way
...
347
As mentioned in a more recent answer, the preferred way is now simply:
const homedir = require...
How can I use getSystemService in a non-activity class (LocationManager)?
...
Krzysiek
4,76233 gold badges2929 silver badges3535 bronze badges
answered Feb 2 '11 at 4:14
Labeeb Panampullan...
Split a string by a delimiter in python
... |
edited Oct 9 '18 at 14:49
Aran-Fey
27.5k55 gold badges6666 silver badges107107 bronze badges
answer...