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Convert tuple to list and back
...t is the homogeneous multidimensional array. It is a table of elements (usually numbers), all of the same type, indexed by a tuple of positive integers.
– pradyunsg
Dec 4 '16 at 3:25
...
Real world use cases of bitwise operators [closed]
...checksums, parity, stop bits, flow control algorithms, and so on, which usually depend on the logic values of individual bytes as opposed to numeric values, since the medium may only be capable of transmitting one bit at a time.
Compression, Encryption
Both of these are heavily dependent on bitwise ...
List directory in Go
... of everything in the current directory (folders are included but not specially marked - you can check if an item is a folder by using the IsDir() method):
package main
import (
"fmt"
"io/ioutil"
"log"
)
func main() {
files, err := ioutil.ReadDir("./")
if err != nil {
...
Splitting string into multiple rows in Oracle
...ct 108 Name, 'test' Project, 'Err1, Err2, Err3' Error from dual
union all
select 109, 'test2', 'Err1' from dual
)
select distinct
t.name, t.project,
trim(regexp_substr(t.error, '[^,]+', 1, levels.column_value)) as error
from
temp t,
table(cast(multiset(select level from dual conne...
Android Notification Sound
...n Codeding
String en_alert, th_alert, en_title, th_title, id;
int noti_all, noti_1, noti_2, noti_3, noti_4 = 0, Langage;
class method
Intent intent = new Intent(context, ReserveStatusActivity.class);
PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, 0);
Notificati...
Eclipse - Unable to install breakpoint due to missing line number attributes
...
The above didn't work for me. I had to click the 'Remove all Breakpoints' icon in the Eclipse > Breakpoints view, then re-add the breakpoints. That worked.
– Vik David
May 19 '11 at 14:05
...
How do I pass a method as a parameter in Python
...thodToRun()
return result
obj.method2(obj.method1)
Note: I believe a __call__() method does exist, i.e. you could technically do methodToRun.__call__(), but you probably should never do so explicitly. __call__() is meant to be implemented, not to be invoked from your own code.
If you wanted me...
Apply multiple functions to multiple groupby columns
...ion.
I recommend making a single custom function that returns a Series of all the aggregations. Use the Series index as labels for the new columns:
def f(x):
d = {}
d['a_sum'] = x['a'].sum()
d['a_max'] = x['a'].max()
d['b_mean'] = x['b'].mean()
d['c_d_prodsum'] = (x['c'] * x['d...
C# 4.0 optional out/ref arguments
Does C# 4.0 allow optional out or ref arguments?
9 Answers
9
...
How do you rename a MongoDB database?
... changes to every shard if the DB is sharded, plus the config servers have all the shard metadata in terms of namespaces with their full names.
There would be absolutely no way to do this on a live system.
To do it offline, it would require re-writing every single database file to accommod...