大约有 43,200 项符合查询结果（耗时：0.0539秒） [XML]
Getting root permissions on a file inside of vi? [closed]
...
10 Answers
10
Active
...
Group by multiple columns in dplyr, using string vector input
...ike so:
data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the columns we want to average within
columns = names(data)[-3]
library(dplyr)
df1 <- data...
Choice between vector::resize() and vector::reserve()
... the only effect.
So it depends on what you want. If you want an array of 1000 default items, use resize(). If you want an array to which you expect to insert 1000 items and want to avoid a couple of allocations, use reserve().
EDIT: Blastfurnace's comment made me read the question again and reali...
How should I handle “No internet connection” with Retrofit on Android
...
answered Mar 23 '14 at 19:22
AlexVAlexV
3,43255 gold badges2727 silver badges3131 bronze badges
...
How to find out which view is focused?
...
113
Call getCurrentFocus() on the Activity.
...
RRSet of type CNAME with DNS name foo.com. is not permitted at apex in zone bar.com
...
As per RFC1912 section 2.4:
A CNAME record is not allowed to coexist with any other data. In
other words, if suzy.podunk.xx is an alias for sue.podunk.xx, you
can't also have an MX record for suzy.podunk.edu, or an A record, or
e...
How do I compile and run a program in Java on my Mac?
...
190
Compiling and running a Java application on Mac OSX, or any major operating system, is very ea...
How to name and retrieve a stash by name in git?
...
21 Answers
21
Active
...
Named Branches vs Multiple Repositories
...
129
The biggest difference is how the branch names are recorded in the history. With named branche...
What's best SQL datatype for storing JSON string?
...
199
Certainly NOT:
TEXT, NTEXT: those types are deprecated as of SQL Server 2005 and should not ...