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Python Pandas: Get index of rows which column matches certain value
...ue
50 True
[3 rows x 1 columns]
If you have a boolean array, mask, and need ordinal index values, you can compute them using np.flatnonzero:
In [110]: np.flatnonzero(df['BoolCol'])
Out[112]: array([0, 3, 4])
Use df.iloc to select rows by ordinal index:
In [113]: df.iloc[np.flatnonzero(df...
How to check if Location Services are enabled?
I'm developing an app on Android OS. I don't know how to check if Location Services are enabled or not.
22 Answers
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Get started with Latex on Linux [closed]
...to produce some output (as a .dvi file to start with, which is possible to convert to many other formats):
latex test.tex
This will print a bunch of output, something like this:
=> latex test.tex
This is pdfeTeX, Version 3.141592-1.21a-2.2 (Web2C 7.5.4)
entering extended mode
(./test.tex
LaTeX2...
Android – Listen For Incoming SMS Messages
I am trying to create an application for monitoring incoming SMS messages, and launch a program via incoming SMS, also it should read the content from the SMS.
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Why aren't pointers initialized with NULL by default?
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We all realize that pointer (and other POD types) should be initialized.
The question then becomes 'who should initialize them'.
Well there are basically two methods:
The compiler initializes them.
The developer initializes them.
Let us assume tha...
ViewPager PagerAdapter not updating the View
...when you call notifyDataSetChanged(), the view pager will remove all views and reload them all. As so the reload effect is obtained.
The second option, suggested by Alvaro Luis Bustamante (previously alvarolb), is to setTag() method in instantiateItem() when instantiating a new view. Then instead o...
Do Java arrays have a maximum size?
...es makes no sense unless we are willing to downvote answers that are plain and simply wrong. Does the difference of five bytes actually matter in the real world, NO, of course not. But it concerns me that people are willing to give an answer "authoritatively" without even trying it to see if it rea...
Unescape HTML entities in Javascript?
...swers given here have a huge disadvantage: if the string you are trying to convert isn't trusted then you will end up with a Cross-Site Scripting (XSS) vulnerability. For the function in the accepted answer, consider the following:
htmlDecode("<img src='dummy' onerror='alert(/xss/)'>");
The...
How does the algorithm to color the song list in iTunes 11 work? [closed]
...ll with distance in the RGB color space.
Therefore, I wrote a function to convert RGB colors (in the form {1,1,1}) to YUV, a color space which is much better at approximating color perception:
(EDIT: @cormullion and @Drake pointed out that Mathematica's built-in CIELAB and CIELUV color spaces woul...
Conventions for exceptions or error codes
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Your fourth point is not a fair one: An error status when converted into an object, can also contain code to check whether the file exists, or is locked, etc. It's simply a variation of stackoverflow.com/a/3157182/632951
– Pacerier
Jul 25 '14 a...