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pandas GroupBy columns with NaN (missing) values
...n the Missing Data section of the docs:
NA groups in GroupBy are automatically excluded. This behavior is consistent with R, for example.
One workaround is to use a placeholder before doing the groupby (e.g. -1):
In [11]: df.fillna(-1)
Out[11]:
a b
0 1 4
1 2 -1
2 3 6
In [12]: df.fil...
What Every Programmer Should Know About Memory?
....
So, any book or article that describes something fundamental cannot be called outdated. "What every programmer should know about memory" is definitely worth to read, but, well, I don't think it's for "every programmer". It's more suitable for system/embedded/kernel guys.
...
wkhtmltopdf: cannot connect to X server
...ble, so no need to make the wrapper script.
– jeffery_the_wind
Mar 13 '12 at 13:43
it worked for me.. in some situatio...
'UserControl' constructor with parameters in C#
Call me crazy, but I'm the type of guy that likes constructors with parameters (if needed), as opposed to a constructor with no parameters followed by setting properties. My thought process: if the properties are required to actually construct the object, they should go in the constructor. I get two...
Why does the default parameterless constructor go away when you create one with parameters
...ass, I most likely want to be able to instantiate that class. In order to allow that, the compiler must add a parameterless constructor, which will have no effect but to allow instantiation. This means that I don't have to include an empty constructor in my code just to make it work.
If I've defin...
Is it considered bad practice to perform HTTP POST without entity body?
...example below) doesn't have a parameter to accept a body.
the method "post_disable_db" just accepts a path parameter "db_name" and doesn't have a 2nd parameter which would imply a mandatory body.
@router.post('/{db_name}/disable',
status_code=HTTP_200_OK,
response_model=R...
Does Go have “if x in” construct similar to Python?
...ion without separate methods for every single type
– Allen
May 13 '15 at 4:33
29
It could be done...
How can I add or update a query string parameter?
... @JarónBarends - Tweak value check to check against undefined and null to allow setting 0 values
Third Update
There was a bug where removing a querystring variable directly before a hashtag would lose the hashtag symbol which has been fixed
Fourth Update
Thanks @rooby for pointing out a regex o...
Sorting a tab delimited file
...u probably want
sort -k4nr file.txt
to sort file.txt by column 4 numerically in reverse order. (Though the data in the question has even 5 fields so the last field would be index 5.)
share
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impr...
Check if URL has certain string with PHP
...URL and the rest check if it contains the word "car".
$url = 'http://' . $_SERVER['SERVER_NAME'] . $_SERVER['REQUEST_URI'];
if (strpos($url,'car') !== false) {
echo 'Car exists.';
} else {
echo 'No cars.';
}
shar...