大约有 20,000 项符合查询结果（耗时：0.0415秒） [XML]
Can dplyr package be used for conditional mutating?
...== 4, g := 3L]
df[a %in% c(2,5,7) | (a==1 & b==4), g := 2L]
Note the order of conditional statements is reversed to get g correctly. There's no copy of g made, even during the second assignment - it's replaced in-place.
On larger data this would have better performance than using nested if-el...
How to run a Runnable thread in Android at defined intervals?
...crease delayed when run long time
3. Solution
To avoid that Just change order of postDelayed(), to avoid delayed:
public void run() {
handler.postDelayed(this, 1000);
tv.append("Hello World");
}
share
|...
Is there a good jQuery Drag-and-drop file upload plugin? [closed]
...h should be the point, try for yourself: plupload.com/example_all_runtimes.php
– Erik Johansson
Nov 3 '11 at 9:46
1
...
Unique ways to use the Null Coalescing operator [closed]
...escing operator means you can write pretty simple comparisons (whether for ordering or equality). For example, using a couple of helper classes in MiscUtil:
public int Compare(Person p1, Person p2)
{
return PartialComparer.Compare(p1.Age, p2.Age)
?? PartialComparer.Compare(p1.Name, p2....
SQL query to get all values a enum can have
...
If enumeration order is important, append ORDER BY e.enumsortorder to the query. The enumerated values will most likely be out of order if new values were inserted into the enumeration type using BEFORE or AFTER.
– Cli...
MySQL - force not to use cache for testing speed of query
...ache in action! Worth the read. databasejournal.com/features/mysql/article.php/3110171/…
– Adrian P.
Feb 20 '14 at 18:03
1
...
How to find the mime type of a file in python?
...ease note, that "above" is a difficult concept in stackoverflow, since the ordering is grouped by votes and ordered randomly inside the groups. I am guessing you refer to @toivotuo's answer.
– Daren Thomas
May 4 '10 at 9:20
...
Accessing a Shared File (UNC) From a Remote, Non-Trusted Domain With Credentials
...
AFAIK, you don't need to map the UNC path to a drive letter in order to establish credentials for a server. I regularly used batch scripts like:
net use \\myserver /user:username password
:: do something with \\myserver\the\file\i\want.xml
net use /delete \\my.server.com
However, an...
Quickly find whether a value is present in a C array?
...
Keep the table in sorted order, and use Bentley's unrolled binary search:
i = 0;
if (key >= a[i+512]) i += 512;
if (key >= a[i+256]) i += 256;
if (key >= a[i+128]) i += 128;
if (key >= a[i+ 64]) i += 64;
if (key >= a[i+ 32]) i += 32...
INSERT with SELECT
...
Sure, what do you want to use for the gid? a static value, PHP var, ...
A static value of 1234 could be like:
INSERT INTO courses (name, location, gid)
SELECT name, location, 1234
FROM courses
WHERE cid = $cid
...