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What does it mean for a data structure to be “intrusive”?
...
boost.org/doc/libs/1_45_0/doc/html/intrusive.html has examples and a good description of pros and cons.
– Tony Delroy
Feb 16 '11 at 6:37
...
How do you remove duplicates from a list whilst preserving order?
.../uniqifiers-benchmark
Fastest one:
def f7(seq):
seen = set()
seen_add = seen.add
return [x for x in seq if not (x in seen or seen_add(x))]
Why assign seen.add to seen_add instead of just calling seen.add? Python is a dynamic language, and resolving seen.add each iteration is more cos...
Is there a command to refresh environment variables from the command prompt in Windows?
...
:SetFromReg
"%WinDir%\System32\Reg" QUERY "%~1" /v "%~2" > "%TEMP%\_envset.tmp" 2>NUL
for /f "usebackq skip=2 tokens=2,*" %%A IN ("%TEMP%\_envset.tmp") do (
echo/set %~3=%%B
)
goto :EOF
:: Get a list of environment variables from registry
:GetRegEnv
"%WinDir%\Syst...
Django South - table already exists
...
Although the table "myapp_tablename" already exists error stop raising
after I did ./manage.py migrate myapp --fake, the DatabaseError shows
no such column: myapp_mymodel.added_field.
Got exactly the same problem!
1.Firstly check the migration...
iOS 7 style Blur view
...[self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[_toolbar]|"
options:0
metrics:0
...
How do you test functions and closures for equality?
...uence language design, so without a quick fix like the now deprecated @objc_block in matt's answer, I would argue that Swift can't properly store and retrieve closures at this time. So I don't think it's appropriate to advocate the use of Swift in callback heavy code like the kind encountered in we...
get list from pandas dataframe column
...hon list. Alternatively you cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
'two': pd.Series([1, 2, 3, 4], index=['a', 'b', 'c', 'd'])}
df = pd.DataFrame(data_dict)
print(f"DataFrame:\n{df}\n")
print(f"column types:\n{df.dtyp...
'id' is a bad variable name in Python
...() is a fundamental built-in:
Help on built-in function id in module
__builtin__:
id(...)
id(object) -> integer
Return the identity of an object. This is guaranteed to be unique among
simultaneously existing objects. (Hint: it's the object's memory
address.)
In g...
Refused to display in a frame because it set 'X-Frame-Options' to 'SAMEORIGIN'
...e in OWIN 3.0 middleware. Refer to this link if you are receiving a "access_denied" error message. blogs.msdn.com/b/webdev/archive/2014/07/02/…
– Ali Hmer
Aug 24 '14 at 15:34
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Changing every value in a hash in Ruby
...ring objects):
# Two ways to achieve the same result (any Ruby version)
my_hash.each{ |_,str| str.gsub! /^|$/, '%' }
my_hash.each{ |_,str| str.replace "%#{str}%" }
If you want the hash to change in place, but you don't want to affect the strings (you want it to get new strings):
# Two ways to ac...