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Using numpy to build an array of all combinations of two arrays
...ion:
@pv's solution
In [113]:
%timeit cartesian(([1, 2, 3], [4, 5], [6, 7]))
10000 loops, best of 3: 135 µs per loop
In [114]:
cartesian(([1, 2, 3], [4, 5], [6, 7]))
Out[114]:
array([[1, 4, 6],
[1, 4, 7],
[1, 5, 6],
[1, 5, 7],
[2, 4, 6],
[2, 4, 7],
[2,...
Selecting with complex criteria from pandas.DataFrame
...00 for x in range(10)]})
>>> df
A B C
0 9 40 300
1 9 70 700
2 5 70 900
3 8 80 900
4 7 50 200
5 9 30 900
6 2 80 700
7 2 80 400
8 5 80 300
9 7 70 800
We can apply column operations and get boolean Series objects:
>>> df["B"] > 50
0 False...
Is ASCII code 7-bit or 8-bit?
... me ASCII is 8-bit character coding scheme. But it is defined only for 0-127 codes which means it can be fit into 7-bits. So can't it be argued that ASCII bit is actually 7-bit code?
...
Iterate a list with indexes in Python
...swear I've seen the function (or method) that takes a list, like this [3, 7, 19] and makes it into iterable list of tuples, like so: [(0,3), (1,7), (2,19)] to use it instead of:
...
How do the post increment (i++) and pre increment (++i) operators work in Java?
...
Does this help?
a = 5;
i=++a + ++a + a++; =>
i=6 + 7 + 7; (a=8)
a = 5;
i=a++ + ++a + ++a; =>
i=5 + 7 + 8; (a=8)
The main point is that ++a increments the value and immediately returns it.
a++ also increments the value (in the background) but returns unchanged value of...
Java 7 language features with Android
Just wondering if anyone has tried using new Java 7 language features with Android?
I know that Android reads the bytecode that Java spits out and turns it to dex. So I guess my question is can it understand the bytecode of Java 7?
...
What's the difference between “mod” and “remainder”?
...
Grijesh Chauhan
51.1k1515 gold badges117117 silver badges179179 bronze badges
answered Dec 3 '12 at 12:54
David SchwartzDavid Schwartz
...
Is it possible to install another version of Python to Virtualenv?
...re able to write too.
You can follow the instructions here.
For Python 2.7.1
Python source
mkdir ~/src
mkdir ~/.localpython
cd ~/src
wget http://www.python.org/ftp/python/2.7.1/Python-2.7.1.tgz
tar -zxvf Python-2.7.1.tgz
cd Python-2.7.1
make clean
./configure --prefix=/home/${USER}/.localpython
...
How to sort Counter by value? - python
...rom collections import Counter
>>> x = Counter({'a':5, 'b':3, 'c':7})
>>> x.most_common()
[('c', 7), ('a', 5), ('b', 3)]
It'll do so in the most efficient manner possible; if you ask for a Top N instead of all values, a heapq is used instead of a straight sort:
>>> x.mo...
Windows 7 SDK installation failure
I seem to be completely unable to install the Windows 7 SDK onto my machine, and the only solution I've found on the web is to make a swathe of registry changes. I've done this - still no success.
...