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Calculating Pearson correlation and significance in Python
...nr(x, y)
Calculates a Pearson correlation coefficient and the p-value for testing
non-correlation.
The Pearson correlation coefficient measures the linear relationship
between two datasets. Strictly speaking, Pearson's correlation requires
that each dataset be normally distributed. Like other ...
Check if database exists in PostgreSQL using shell
...e special variable $? to the exit status of the last command. You can also test the status directly in a conditional:
if psql -lqt | cut -d \| -f 1 | grep -qw <db_name>; then
# database exists
# $? is 0
else
# ruh-roh
# $? is 1
fi
...
What are some examples of commonly used practices for naming git branches? [closed]
...nge. I do not know what your cycles are, but let's assume they are 'new', 'testing' and 'verified'. You can name your branches with abbreviated versions of these tags, always spelled the same way, to both group them and to remind you which stage you're in.
new/frabnotz
new/foo
new/bar
test/foo
tes...
What is the overhead of creating a new HttpClient per call in a WebAPI client?
... new HttpClient requires re-establishing a new TCP/IP connection.
From my tests, using plain HTTP on a LAN, the performance hit is fairly negligible. I suspect this is because there is an underlying TCP keepalive that is holding the connection open even when HttpClientHandler tries to close it.
...
Jackson serialization: ignore empty values (or null)
...ON_NULL)
if you are dealing with jackson with version below 2+ (1.9.5) i tested it, you can easily use this annotation above the class. Not for specified for the attributes, just for class decleration.
share
|
...
Rails Object to hash
... @post.as_json
puts hash.pretty_inspect
Will output :
{
:name => "test",
:post_number => 20,
:active => true
}
To go a bit further, you could override that method in order to customize the way your attributes appear, by doing something like this :
class Post < ActiveRecord::...
JavaScript check if variable exists (is defined/initialized)
...
'if( variable )' also fails for testing for the existence of object properties.
– scotts
May 4 '10 at 22:40
55
...
Meaning of epsilon argument of assertEquals for double values
I have a question about junit assertEquals to test double values. Reading the API doc I can see:
7 Answers
...
Checking if an object is a given type in Swift
...ive types, the superclass would be Any. Here is an example:
21> func test (obj:Any) -> String {
22. if obj is Int { return "Int" }
23. else if obj is String { return "String" }
24. else { return "Any" }
25. }
...
30> test (1)
$R16: String = "Int"
31> test ("abc")...
Is there a way to 'uniq' by column?
...
-u for unique
-t, so comma is the delimiter
-k1,1 for the key field 1
Test result:
overflow@domain2.com,2009-11-27 00:58:29.793000000,xx3.net,255.255.255.0
stack2@domain.com,2009-11-27 01:05:47.893000000,xx2.net,127.0.0.1
...