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Use a list of values to select rows from a pandas dataframe [duplicate]
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You can use isin method:
In [1]: df = pd.DataFrame({'A': [5,6,3,4], 'B': [1,2,3,5]})
In [2]: df
Out[2]:
A B
0 5 1
1 6 2
2 3 3
3 4 5
In [3]: df[df['A'].isin([3, 6])]
Out[3]:
A B
1 6 2
2 3 3
And to get the opposite use ~:
In [4]: df[~df['A'].isin([3, 6])]
Out[4]:
A B...
error: cannot dynamic_cast ‘b’ (of type ‘class Base*’) to type ‘c...
error: cannot dynamic_cast ‘b’ (of type ‘class Base*’) to type ‘class Derived*’ (source type is not polymorphic)在将父类型转换为子类型时,可以使用static_cast和dynamic_cast.如果使用dynamic_cast,它要求父类必须为多态的,即要求至少有一个虚函数,因此....
Debian/Linux下安装OpenJDK8 - 操作系统(内核) - 清泛网 - 专注C/C++及内核技术
Debian/Linux下安装OpenJDK8linux_install_openjdk8因为Debian11的源里不再带OpenJDK8了，需要手工来安装。下载安装包因为手工安装，所以部分依赖包需要自己下载。wget http: snapshot debian org archive debian-security 202202 因为Debian11的源里不再带Open...
how do i remove a comma off the end of a string?
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Manse
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answered Oct 29 '09 at 10:18
SigurdSigurd
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How to empty a list?
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This actually removes the contents from the list, but doesn't replace the old label with a new empty list:
del lst[:]
Here's an example:
lst1 = [1, 2, 3]
lst2 = lst1
del lst1[:]
print(lst2)
For the sake of completeness, the slice assignment has the same effect:
lst[:]...
What does the ^ operator do in Java?
... exclusive-or ("xor") operator.
Let's take 5^6 as example:
(decimal) (binary)
5 = 101
6 = 110
------------------ xor
3 = 011
This the truth table for bitwise (JLS 15.22.1) and logical (JLS 15.22.2) xor:
^ | 0 1 ^ | F T
--+----- --+-----
0 | 0 1 F |...
month name to month number and vice versa in python
I am trying to create a function that can convert a month number to an abbreviated month name or an abbreviated month name to a month number. I thought this might be a common question but I could not find it online.
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How do you return from 'gf' in Vim
I am using Vim for windows installed in Unix mode. Thanks to this site I now use the gf command to go to a file under the cursor.
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Can someone give an example of cosine similarity, in a very simple, graphical way?
...se texts are, purely in terms of word counts (and ignoring word order). We begin by making a list of the words from both texts:
me Julie loves Linda than more likes Jane
Now we count the number of times each of these words appears in each text:
me 2 2
Jane 0 1
Julie 1 1
Linda 1...
How to force 'cp' to overwrite directory instead of creating another one inside?
I'm trying to write a Bash script that will overwrite an existing directory. I have a directory foo/ and I am trying to overwrite bar/ with it. But when I do this:
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