大约有 40,000 项符合查询结果（耗时：0.0347秒） [XML]
Are tuples more efficient than lists in Python?
...2]
...
>>> import dis
>>> dis.dis(a)
2 0 LOAD_CONST 1 (1)
3 LOAD_CONST 2 (2)
6 LOAD_CONST 3 (3)
9 LOAD_CONST 4 (4)
12 LOAD_CONST 5 (5)
...
How to include JavaScript file or library in Chrome console?
...s answer, I wrapped it around a JS function and use it as follows ... var _loadScript = function(path){ var script= document.createElement('script'); script.type= 'text/javascript'; script.src= path; document.head.appendChild(script); } _loadScript('documentcloud.github.com/underscore/undersco...
Paging UICollectionView by cells, not screen
...nformance and set a value for pageWidth:
func scrollViewWillBeginDragging(_ scrollView: UIScrollView) {
let pageWidth = // The width your page should have (plus a possible margin)
let proportionalOffset = collectionView.contentOffset.x / pageWidth
indexOfCellBeforeDragging = Int(round(p...
Standardize data columns in R
...
z = runif(10, 10, 20))
dat
dat2 <- dat %>% mutate_at(c("y", "z"), ~(scale(.) %>% as.vector))
dat2
which gives me this:
> dat
x y z
1 29.75859 3.633225 14.56091
2 30.05549 3.605387 12.65187
3 30.21689 3.318092 13.04672
4 29.53086 3.079992...
Using curl to upload POST data with files
... I think its really useful.
public function postFile()
{
$file_url = "test.txt"; //here is the file route, in this case is on same directory but you can set URL too like "http://examplewebsite.com/test.txt"
$eol = "\r\n"; //default line-break for mime type
$BOUNDARY = m...
Insert into … values ( SELECT … FROM … )
...SERT from another table I did the following in SQLite3:
INSERT INTO column_1 ( val_1, val_from_other_table )
VALUES('val_1', (SELECT val_2 FROM table_2 WHERE val_2 = something))
share
|
improve ...
How to drop all tables in a SQL Server database?
...ECLARE @Sql NVARCHAR(500) DECLARE @Cursor CURSOR
SET @Cursor = CURSOR FAST_FORWARD FOR
SELECT DISTINCT sql = 'ALTER TABLE [' + tc2.TABLE_SCHEMA + '].[' + tc2.TABLE_NAME + '] DROP [' + rc1.CONSTRAINT_NAME + '];'
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS rc1
LEFT JOIN INFORMATION_SCHEMA.TABLE_...
What is the Scala annotation to ensure a tail recursive function is optimized?
...e to Scala version 2.8.0.RC5 (Java HotSpot(TM) 64-Bit Server VM, Java 1.6.0_18).
Type in expressions to have them evaluated.
Type :help for more information.
scala> import scala.annotation.tailrec
import scala.annotation.tailrec
scala> class Tails {
| @tailrec def boom(x: Int): Int = {
...
Using the HTML5 “required” attribute for a group of checkboxes?
...="checkbox-group required">
<input type="checkbox" name="checkbox_name[]">
<input type="checkbox" name="checkbox_name[]">
<input type="checkbox" name="checkbox_name[]">
<input type="checkbox" name="checkbox_name[]">
</div>
You can use this expressio...
What is the difference between JSON and Object Literal Notation?
...t
console.log('Object Literal : ', objLiteral ); // Object {foo: 42}foo: 42__proto__: Object
// This is a JSON String, like what you'd get back from an AJAX request.
var jsonString = '{"foo": 452}';
console.log('JOSN String : ', jsonString ); // {"foo": 452}
// This is how you deserialize that JSO...