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How to filter Pandas dataframe using 'in' and 'not in' like in SQL
...where)
As a worked example:
import pandas as pd
>>> df
country
0 US
1 UK
2 Germany
3 China
>>> countries_to_keep
['UK', 'China']
>>> df.country.isin(countries_to_keep)
0 False
1 True
2 False
3 True
Name: country, dtype: bool
>>>...
Matplotlib discrete colorbar
...rm as normalizer for your scatter. The quirky bit (in my method) is making 0 showup as grey.
For images i often use the cmap.set_bad() and convert my data to a numpy masked array. That would be much easier to make 0 grey, but i couldnt get this to work with the scatter or the custom cmap.
As an ...
Convert column classes in data.table
...
105
For a single column:
dtnew <- dt[, Quarter:=as.character(Quarter)]
str(dtnew)
Classes ‘d...
CMFCTabCtrl的使用、颜色样式调整 - C/C++ - 清泛网 - 专注C/C++及内核技术
...FCTabCtrl::LOCATION_TOP);
m_wnd1.Create (WS_CHILD | WS_VISIBLE, CRect (0, 0, 0, 0), &m_wndTab, 1);
m_wnd1.SetFont (&afxGlobalData.fontRegular);
m_wnd1.SetWindowText (_T("Edit 1"));
m_wnd2.Create (WS_CHILD | WS_VISIBLE, CRect (0, 0, 0, 0), &m_wndTab, 2);
m_wnd2.SetFont (&afxGlobalData.font...
Is it worth using Python's re.compile?
...
I've had a lot of experience running a compiled regex 1000s of times versus compiling on-the-fly, and have not noticed any perceivable difference. Obviously, this is anecdotal, and certainly not a great argument against compiling, but I've found the difference to be negligible.
...
What does `someObject.new` do in Java?
...
120
It's the way to instantiate a non-static inner class from outside the containing class body, as ...
How to convert number to words in java
...
107
Here is the code, I don't think there is any method in SE.
It basically converts number to str...
How many double numbers are there between 0.0 and 1.0?
...e), there will therefore be 2 to the 52th power different doubles (i.e., 4503599627370496 of them). For example, that's the number of distinct doubles between 0.5 included and 1.0 excluded, and exactly that many also lie between 1.0 included and 2.0 excluded, and so forth.
Counting the doubles bet...
What is “2's Complement”?
...e to think of the numbers in binary.
It basically says,
for zero, use all 0's.
for positive integers, start counting up, with a maximum of 2(number of bits - 1)-1.
for negative integers, do exactly the same thing, but switch the role of 0's and 1's (so instead of starting with 0000, start with 1111...
Grep characters before and after match?
... characters after
$> echo "some123_string_and_another" | grep -o -P '.{0,3}string.{0,4}'
23_string_and
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