大约有 23,000 项符合查询结果（耗时：0.0356秒） [XML]
Cron job every three days
... out, you can use date('k') to get the day of the year instead of doing it based on the day of the month.
share
|
improve this answer
|
follow
|
...
Assign output to variable in Bash
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
Draft saved
Draft discarded
...
windows batch SET inside IF not working
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
Draft saved
Draft discarded
...
filter for complete cases in data.frame using dplyr (case-wise deletion)
...s(.))
or this:
library(tidyr)
df %>% drop_na
If you want to filter based on one variable's missingness, use a conditional:
df %>% filter(!is.na(x1))
or
df %>% drop_na(x1)
Other answers indicate that of the solutions above na.omit is much slower but that has to be balanced against...
WKWebView in Interface Builder
...
Here's a simple Swift 3 version based on crx_au's excellent answer.
import WebKit
class WKWebView_IBWrapper: WKWebView {
required convenience init?(coder: NSCoder) {
let config = WKWebViewConfiguration()
//config.suppressesIncremental...
What is a good reason to use SQL views?
...o a single virtual table
Views can act as aggregated tables, where the database engine aggregates
data (sum, average etc) and presents the calculated results as part of the data
Views can hide the complexity of data; for example a view could appear as
Sales2000 or Sales2001, transparently partit...
Number of days between two dates in Joda-Time
...ion is JSR 310.
You may exchange java.time objects directly with your database. Use a JDBC driver compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes.
Where to obtain the java.time classes?
Java SE 8, Java SE 9, Java SE 10, and later
Built-in.
Part of the st...
How to delete items from a dictionary while iterating over it?
...;>> mydict
{'four': 4, 'three': 3, 'one': 1}
If you need to delete based on the items value, use the items() method instead:
>>> for k, v in mydict.items():
... if v == 3:
... del mydict[k]
...
>>> mydict
{'four': 4, 'one': 1}
...
Xcode : failed to get the task for process
...
Based on my current search, the error "Failed to get the task for process" at xcode 5 could happen for multiple reasons:
One is that we are debugging an application which is signed with distribution ad-hoc provision profile...
what is the difference between 'transform' and 'fit_transform' in sklearn
... transformation.
But for testing set, Machine learning applies prediction based on what was learned during the training set and so it doesn't need to calculate, it just performs the transformation.
share
|
...