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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 >>&gt...
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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 ...
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Convert column classes in data.table

... 105 For a single column: dtnew <- dt[, Quarter:=as.character(Quarter)] str(dtnew) Classes ‘d...
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Could not load file or assembly 'System.Net.Http.Formatting' or one of its dependencies. The system

... dll's I need for my MVC program. EDIT >>> For Visual Studio 2013 and above, step 2) should read: Open Visual Studio and go to Tools > Options > NuGet Package Manager and on the right hand side there is a "Clear Package Cache button". Click this button and make sure that the che...
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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. ...
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Grep characters before and after match?

... characters after $> echo "some123_string_and_another" | grep -o -P '.{0,3}string.{0,4}' 23_string_and share | improve this answer | follow | ...
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micro:bit 实验08 - 摇一摇与倾斜检测 · App Inventor 2 中文网

...索 micro:bit 实验08 - 摇一摇与倾斜检测 实验08:摇一摇与倾斜检测 这个实验做完你会得到什么 一、器材清单 二、界面组件 三、分步...
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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 ...
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Compare floats in php

...ou need to use a smallest acceptable difference: if (abs(($a-$b)/$b) < 0.00001) { echo "same"; } Something like that. share | improve this answer | follow ...
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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...