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How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
...er pandas:]
You could use the function isnull instead of the method:
In [56]: df = pd.DataFrame([range(3), [0, np.NaN, 0], [0, 0, np.NaN], range(3), range(3)])
In [57]: df
Out[57]:
0 1 2
0 0 1 2
1 0 NaN 0
2 0 0 NaN
3 0 1 2
4 0 1 2
In [58]: pd.isnull(df)
Out[58]:
...
Index all *except* one item in python
...
115
For a list, you could use a list comp. For example, to make b a copy of a without the 3rd eleme...
Python and pip, list all versions of a package that's available?
...re available:
$ pip install yolk3k
$ yolk -V django
Django 1.3
Django 1.2.5
Django 1.2.4
Django 1.2.3
Django 1.2.2
Django 1.2.1
Django 1.2
Django 1.1.4
Django 1.1.3
Django 1.1.2
Django 1.0.4
yolk3k is a fork of the original yolk which ceased development in 2012. Though yolk is no longer maintaine...
Why does Math.round(0.49999999999999994) return 1?
In the following program you can see that each value slightly less than .5 is rounded down, except for 0.5 .
5 Answers
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How to validate an Email in PHP?
How can I validate the input value is a valid email address using php5. Now I am using this code
7 Answers
...
pandas: filter rows of DataFrame with operator chaining
...the boolean index.
In [96]: df
Out[96]:
A B C D
a 1 4 9 1
b 4 5 0 2
c 5 5 1 0
d 1 3 9 6
In [99]: df[(df.A == 1) & (df.D == 6)]
Out[99]:
A B C D
d 1 3 9 6
If you want to chain methods, you can add your own mask method and use that one.
In [90]: def mask(df, ke...
Using async/await for multiple tasks
...
591
int[] ids = new[] { 1, 2, 3, 4, 5 };
Parallel.ForEach(ids, i => DoSomething(1, i, blogClien...
App Inventor 2 数学代码块 · App Inventor 2 中文网
...(abs)
返回给定数字的绝对值。如：-3.3 的绝对值是 3.3，5 的绝对值是 5，0 的绝对值是 0。
相反数 (neg)
返回给定数字的负数，若给定负数则返回正数。如：8 返回 -8，-0.7 返回 0.7，0 则仍然返回 0。
对数 (log)
返回给定数...
What is the bower (and npm) version syntax?
...
5 Answers
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