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How to update gradle in android studio?
I installed Android Studio 0.1.9. Today I got and update to version 0.2 and of course I updated. After the installation I restarted Android Studio but now I get this message:
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Why does ~True result in -2?
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int(True) is 1.
1 is:
00000001
and ~1 is:
11111110
Which is -2 in Two's complement1
1 Flip all the bits, add 1 to the resulting number and interpret the result as a binary representation of the magnitude and add a negative sign (s...
What causes imported Maven project in Eclipse to use Java 1.5 instead of Java 1.6 by default and how
I imported a Maven project and it used Java 1.5 even though I have 1.6 configured as my Eclipse default Preferences->Java->Installed JREs .
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Difference between `set`, `setq`, and `setf` in Common Lisp?
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173
Originally, in Lisp, there were no lexical variables -- only dynamic ones. And
there was no SE...
How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
...0, 0, np.NaN], range(3), range(3)])
>>> df.isnull()
0 1 2
0 False False False
1 False True False
2 False False True
3 False False False
4 False False False
>>> df.isnull().any(axis=1)
0 False
1 True
2 True
3 False
4 False
dtype: bo...
Why can't R's ifelse statements return vectors?
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100
The documentation for ifelse states:
ifelse returns a value with the same
shape as test ...
Counting the number of elements with the values of x in a vector
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18 Answers
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calculating the difference in months between two dates
...o months difference? If you say it should yield one, then what about July 31, 2009 and August 1, 2009? Is that a month? Is it simply the difference of the Month values for the dates, or is it more related to an actual span of time? The logic for determining all of these rules is non-trivial, so you'...