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What does the ^ operator do in Java?
...perator.
Let's take 5^6 as example:
(decimal) (binary)
5 = 101
6 = 110
------------------ xor
3 = 011
This the truth table for bitwise (JLS 15.22.1) and logical (JLS 15.22.2) xor:
^ | 0 1 ^ | F T
--+----- --+-----
0 | 0 1 F | F T
1 | 1 0 T | T...
How to get a value from a cell of a dataframe?
...ue using the column name:
In [3]: sub_df
Out[3]:
A B
2 -0.133653 -0.030854
In [4]: sub_df.iloc[0]
Out[4]:
A -0.133653
B -0.030854
Name: 2, dtype: float64
In [5]: sub_df.iloc[0]['A']
Out[5]: -0.13365288513107493
...
Does ruby have real multithreading?
...
Updated with Jörg's Sept 2011 comment
You seem to be confusing two very different things here: the
Ruby Programming Language and the specific threading model of one
specific implementation of the Ruby Programming Language. There
are currently arou...
TCP: can two different sockets share a port?
...
answered Jun 20 '12 at 23:32
Remy LebeauRemy Lebeau
417k2626 gold badges335335 silver badges578578 bronze badges
...
Understanding “randomness”
...ough a pseudo-random variable:
BarChart[BinCounts[RandomReal[{0, 1}, 50000], 0.01]]
While this is the distribution you get after multiplying two random variables:
BarChart[BinCounts[Table[RandomReal[{0, 1}, 50000] *
RandomReal[{0, 1}, 500...
Validate that a string is a positive integer
...
302
Two answers for you:
Based on parsing
Regular expression
Note that in both cases, I've inte...
What Process is using all of my disk IO
...
You're looking for iotop (assuming you've got kernel >2.6.20 and Python 2.5). Failing that, you're looking into hooking into the filesystem. I recommend the former.
share
|
improve...
How to validate an email address in JavaScript
...^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
return re.test(String(email).toLowerCase());
}
Here's the example of regular expresion that accepts unicode:
const re = /^(([^<&...
CSS Background Opacity [duplicate]
..., or use an RGBa (a for alpha) color for your background color.
Example, 50% faded black background:
<div style="background-color:rgba(0, 0, 0, 0.5);">
<div>
Text added.
</div>
</div>
...
Fast permutation -> number -> permutation mapping algorithms
...ake of an example, let's say, 7 elements, 1234567. I know there are 7! = 5040 permutations possible of these 7 elements.
1...