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bash/fish command to print absolute path to a file
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answered Oct 12 '10 at 13:16
Benjamin BannierBenjamin Bannier
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Global and local variables in R
...ope of variables. For instance, in the following code snippet:
if (x > 10) {
y <- 0
}
else {
y <- 1
}
y remains accessible after the if-else statement.
As you well say, you can also create nested environments. You can have a look at these two links for understanding how to use t...
Efficiently checking if arbitrary object is NaN in Python / numpy / pandas?
...you won't need to specify the dtype)
In [24]: s = Series([Timestamp('20130101'),np.nan,Timestamp('20130102 9:30')],dtype='M8[ns]')
In [25]: s
Out[25]:
0 2013-01-01 00:00:00
1 NaT
2 2013-01-02 09:30:00
dtype: datetime64[ns]``
In [26]: pd.isnull(s)
Out[26]:
0 False
1 ...
How to delete last character in a string in C#?
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10 Answers
10
Active
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python pandas: Remove duplicates by columns A, keeping the row with the highest value in column B
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This takes the last. Not the maximum though:
In [10]: df.drop_duplicates(subset='A', keep="last")
Out[10]:
A B
1 1 20
3 2 40
4 3 10
You can do also something like:
In [12]: df.groupby('A', group_keys=False).apply(lambda x: x.loc[x.B.idxmax()])
Out[12]:
A ...
Why does running the Flask dev server run itself twice?
...eters
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2
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Is it safe to ignore the possibility of SHA collisions in practice?
...than 2n/2). For instance, with SHA-256 (n=256) and one billion messages (p=109) then the probability is about 4.3*10-60.
A mass-murderer space rock happens about once every 30 million years on average. This leads to a probability of such an event occurring in the next second to about 10-15. That's ...
How to securely store access token and secret in Android?
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edited Jun 10 at 8:04
CoolMind
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Can I add a UNIQUE constraint to a PostgreSQL table, after it's already created?
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edited Aug 2 '17 at 10:42
a_horse_with_no_name
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Mongo: find items that don't have a certain field
...owLowRepImageUploadWarning: true,
reputationToPostImages: 10,
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postfix: "",
imageUploader: {
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