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How to select rows from a DataFrame based on column values?
... 2 4
4 foo two 4 8
6 foo one 6 12
7 foo three 7 14
If you have multiple values you want to include, put them in a
list (or more generally, any iterable) and use isin:
print(df.loc[df['B'].isin(['one','three'])])
yields
A B C D
0 foo one 0 0
1 bar o...
Android: create a popup that has multiple selection options
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Hello, can you also show how I can set actions for specific item selections? Example: I want to let the user change the app language by clicking one of those items (probably using if statement).
– Arda Çebi
Feb 7 '18 at 20:11
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How to check type of variable in Java?
...uble) these are all primitives, and there are no sub-types of them. Thus, if you declare a variable to be an int:
int x;
You can be sure it will only ever hold int values.
If you declared a variable to be a List, however, it is possible that the variable will hold sub-types of List. Examples o...
A semantics for Bash scripts?
... its own right, but with features designed to make it easy to interact specifically with the operating system and filesystem. The POSIX shell's (hereafter referred to just as "the shell") semantics are a bit of a mutt, combining some features of LISP (s-expressions have a lot in common with shell wo...
Disable building workspace process in Eclipse
... i disable it because it is taking a long time to complete and i dont know if it is necessary. Thank you
4 Answers
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What's a standard way to do a no-op in python?
I often find myself writing if / elif / else constructs in python, and I want to include options which can occur, but for which the corresponding action is to do nothing. I realise I could just exclude those if statements, but for readability I find it helps to include them all, so that if you are l...
How to find a hash key containing a matching value
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@Coderama The difference between find and select is that find returns the first match and select (which is aliased by findAll) returns all matches.
– Daniel Vandersluis
Sep 25 '10 at 13:48
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Objective-C Runtime: best way to check if class conforms to protocol?
I have a Class (but no instance) and need to know if it conforms to a certain protocol. However, Class can be subclassed several times and class_conformsToProtocol() ignores protocols declared on superclasses.
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What's the best way to detect a 'touch screen' device using JavaScript?
...uery plug-in that's for use on both desktop and mobile devices. I wondered if there is a way with JavaScript to detect if the device has touch screen capability. I'm using jquery-mobile.js to detect the touch screen events and it works on iOS, Android etc., but I'd also like to write conditional sta...
Sorting a set of values [closed]
...o store the numbers as numbers rather than strings in the first place. But if not, you just need to use a key function:
>>> sorted(s, key=float)
['0.000000000', '0.009518000', '0.018384000', '0.030810999', '4.918560000', '10.277200999']
For more information, see the Sorting HOWTO in th...