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Separation of business logic and data access in django
...
+100
It seems like you are asking about the difference between the data model and the domain model – the latter is where you can find ...
How to make a great R reproducible example
...
Example:
# sample data
DF <- data.frame(id=rep(LETTERS, each=4)[1:100], replicate(100, sample(1001, 100)), Class=sample(c("Yes", "No"), 100, TRUE))
DF is about 100 x 102. I want to sample 10 rows, and a few specific columns
reproduce(DF, cols=c("id", "X1", "X73", "Class")) # I could al...
How to vertically center a container in Bootstrap?
...gt;
...
</div>
</div>
.vertical-center {
min-height: 100%; /* Fallback for browsers do NOT support vh unit */
min-height: 100vh; /* These two lines are counted as one :-) */
display: flex;
align-items: center;
}
Important notes (Considered in the demo):
A perc...
How to spyOn a value property (rather than a method) with Jasmine
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100
In February 2017, they merged a PR adding this feature, they released in April 2017.
so to s...
Heroku free account limited?
...o requests. If each instance of your application can serve each request in 100ms, then you get 600 requests/minute with the free account.
Your application code and its assets (the slug) are limited to 300 MB in total. Your application also has access to the local filesystem, which can serve as an e...
JFrame in full screen Java
....
Dimension dim = Toolkit.getDefaultToolkit().getScreenSize();
setBounds(100, 100, (int) dim.getWidth(), (int) dim.getHeight());
setLocationRelativeTo(null);
But this has pitfalls in Ubuntu OS. The work around I found was this.
if (SystemHelper.isUnix()) {
getContentPane().setPreferredSize(...
Base64 encoding in SQL Server 2005 T-SQL
...ing the use of variables in both instances.
DECLARE
@EncodeIn VARCHAR(100) = 'Test String In',
@EncodeOut VARCHAR(500),
@DecodeOut VARCHAR(200)
SELECT @EncodeOut =
CAST(N'' AS XML).value(
'xs:base64Binary(xs:hexBinary(sql:column("bin")))'
, 'VARCHAR(MAX)'
...
What is the equivalent of the C# 'var' keyword in Java?
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Since lombok v1.16.12 there is also experimental support for var. projectlombok.org/features/experimental/var.html
– Roel Spilker
May 29 '17 at 18:26
...
time.sleep — sleeps thread or process?
...sleep(1)
class waiter(Thread):
def run(self):
for x in xrange(100,103):
print x
time.sleep(5)
def run():
worker().start()
waiter().start()
Which will print:
>>> thread_test.run()
0
100
>>> 1
2
3
4
5
101
6
7
8
9
10
102
...
Remove duplicated rows
... unique(DF) 44708.230 48981.8445 53062.536 51573.276 52844.591 107032.18 100 b
# unique(DT) 746.855 776.6145 2201.657 864.932 919.489 55986.88 100 a
microbenchmark(duplicated(DF), duplicated(DT))
# Unit: microseconds
# expr min lq mean median ...