大约有 47,000 项符合查询结果（耗时：0.0696秒） [XML]
Round to at most 2 decimal places (only if necessary)
...
Use Math.round(num * 100) / 100
Edit: to ensure things like 1.005 round correctly, we use
Math.round((num + Number.EPSILON) * 100) / 100
share
|
...
How do I select elements of an array given condition?
...
answered Jun 13 '10 at 0:50
jfsjfs
326k132132 gold badges817817 silver badges14381438 bronze badges
...
Operation on every pair of element in a list
...
|
edited Jun 3 '09 at 18:12
answered Jun 3 '09 at 0:24
...
What's the difference between echo, print, and print_r in PHP?
...s you have in your variables. Consider this test program:
$values = array(0, 0.0, false, '');
var_dump($values);
print_r ($values);
With print_r you can't tell the difference between 0 and 0.0, or false and '':
array(4) {
[0]=>
int(0)
[1]=>
float(0)
[2]=>
bool(false)
[3]=...
Why does multiprocessing use only a single core after I import numpy?
...
150
After some more googling I found the answer here.
It turns out that certain Python modules (num...
PHP shell_exec() vs exec()
...
Daniel A. WhiteDaniel A. White
170k4242 gold badges334334 silver badges403403 bronze badges
...
How do I check the difference, in seconds, between two dates?
...tes, use total_seconds like this:
import datetime as dt
a = dt.datetime(2013,12,30,23,59,59)
b = dt.datetime(2013,12,31,23,59,59)
(b-a).total_seconds()
86400.0
#note that seconds doesn't give you what you want:
(b-a).seconds
0
...
How to synchronize a static variable among threads running different instances of a class in Java?
...s on the class object.
public class Test {
private static int count = 0;
public static synchronized void incrementCount() {
count++;
}
}
Explicitly synchronize on the class object.
public class Test {
private static int count = 0;
public void incrementCount() {
...
How to deal with SettingWithCopyWarning in Pandas?
I just upgraded my Pandas from 0.11 to 0.13.0rc1. Now, the application is popping out many new warnings. One of them like this:
...
How to run a background task in a servlet based web application?
...ples:
@Singleton
public class BackgroundJobManager {
@Schedule(hour="0", minute="0", second="0", persistent=false)
public void someDailyJob() {
// Do your job here which should run every start of day.
}
@Schedule(hour="*/1", minute="0", second="0", persistent=false)
pu...