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Python pandas Filtering out nan from a data selection of a column of strings
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Just drop them:
nms.dropna(thresh=2)
this will drop all rows where there are at least two non-NaN.
Then you could then drop where name is NaN:
In [87]:
nms
Out[87]:
movie name rating
0 thg John 3
1 thg NaN 4
3 mol Graham NaN
4 lob N...
Why is whitespace sometimes needed around metacharacters?
...s a list of characters that separate tokens in BASH. These characters are called metacharacters and they are |, &, ;, (, ), <, >, space and tab. On the other hand, curly braces ({ and }) are just ordinary characters that make up words.
Omitting the second space before } will do, since &am...
What are the differences between vector and list data types in R?
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Technically lists are vectors, although very few would use that term. "list" is one of several modes, with others being "logical", "character", "numeric", "integer". What you are calling vectors are "atomic vectors" in strict R parl...
Why do access tokens expire?
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This is very much implementation specific, but the general idea is to allow providers to issue short term access tokens with long term refresh tokens. Why?
Many providers support bearer tokens which are very weak security-wise. By making them short-lived and requiring refresh, they limit the ...
connect local repo with remote repo
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git remote add origin <remote_repo_url>
git push --all origin
If you want to set all of your branches to automatically use this remote repo when you use git pull, add --set-upstream to the push:
git push --all --set-upstream origin
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Flask SQLAlchemy query, specify column names
... do I specify the column that I want in my query using a model (it selects all columns by default)? I know how to do this with the sqlalchmey session: session.query(self.col1) , but how do I do it with with models? I can't do SomeModel.query() . Is there a way?
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Cleaning `Inf` values from an R dataframe
...ption 1
Use the fact that a data.frame is a list of columns, then use do.call to recreate a data.frame.
do.call(data.frame,lapply(DT, function(x) replace(x, is.infinite(x),NA)))
Option 2 -- data.table
You could use data.table and set. This avoids some internal copying.
DT <- data.table(dat)...
Why is 'false' used after this simple addEventListener function?
...es that the user wishes to
initiate capture. After initiating
capture, all events of the specified
type will be dispatched to the
registered listener before being
dispatched to any EventTargets beneath
it in the DOM tree. Events which are
bubbling upward through the tree will
not tri...
How to select following sibling/xml tag using xpath
I have an HTML file (from Newegg) and their HTML is organized like below. All of the data in their specifications table is ' desc ' while the titles of each section are in ' name. ' Below are two examples of data from Newegg pages.
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Sass calculate percent minus px
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I would say that calc() does not at all work in most browsers. Mobile platforms are just as important as desktops.
– dalgard
Feb 7 '13 at 15:10
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