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How to return result of a SELECT inside a function in PostgreSQL?
...
Use RETURN QUERY:
CREATE OR REPLACE FUNCTION word_frequency(_max_tokens int)
RETURNS TABLE (txt text -- also visible as OUT parameter inside function
, cnt bigint
, ratio bigint) AS
$func$
BEGIN
RETURN QUERY
SELECT t.txt
,...
What is __pycache__?
... it to bytecode first (this is an oversimplification) and stores it in the __pycache__ folder. If you look in there you will find a bunch of files sharing the names of the .py files in your project's folder, only their extensions will be either .pyc or .pyo. These are bytecode-compiled and optimized...
How to print a groupby object
...
Simply do:
grouped_df = df.groupby('A')
for key, item in grouped_df:
print(grouped_df.get_group(key), "\n\n")
This also works,
grouped_df = df.groupby('A')
gb = grouped_df.groups
for key, values in gb.iteritems():
print(df.ix[...
How to use single storyboard uiviewcontroller for multiple subclass
...
The code of line we are looking for is:
object_setClass(AnyObject!, AnyClass!)
In Storyboard -> add UIViewController give it a ParentVC class name.
class ParentVC: UIViewController {
var type: Int?
override func awakeFromNib() {
if type = 0 {
...
How to check if a file exists in Go?
...doesn't exist, equivalent to Python's if not os.path.exists(filename):
if _, err := os.Stat("/path/to/whatever"); os.IsNotExist(err) {
// path/to/whatever does not exist
}
To check if a file exists, equivalent to Python's if os.path.exists(filename):
Edited: per recent comments
if _, err := o...
Docker how to change repository name or rename image?
...
Note that you probably want docker image tag from_server:version to_server:version as described here: docs.docker.com/engine/reference/commandline/image_tag
– Traveler
Mar 21 '19 at 0:49
...
Move capture in lambda
...e following will be legal code in C++14:
using namespace std;
// a unique_ptr is move-only
auto u = make_unique<some_type>( some, parameters );
// move the unique_ptr into the lambda
go.run( [ u{move(u)} ] { do_something_with( u ); } );
But it is much more general in the sense that cap...
What encoding/code page is cmd.exe using?
...te static final String BOM = "\ufeff";
private static final String TEST_STRING
= "ASCII abcde xyz\n"
+ "German äöü ÄÖÜ ß\n"
+ "Polish ąęźżńł\n"
+ "Russian абвгдеж эюя\n"
+ "CJK 你好\n";
public static void mai...
How do I create a link using javascript?
...answered Jan 23 '11 at 8:50
gion_13gion_13
38.3k99 gold badges9090 silver badges101101 bronze badges
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Serializing class instance to JSON
...N for your class.
A simple solution would be to call json.dumps() on the .__dict__ member of that instance. That is a standard Python dict and if your class is simple it will be JSON serializable.
class Foo(object):
def __init__(self):
self.x = 1
self.y = 2
foo = Foo()
s = js...