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while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
...oes.
Here's 2.7:
>>> dis.dis('True == 1')
1 0 LOAD_GLOBAL 0 (True)
3 LOAD_CONST 1 (1)
6 COMPARE_OP 2 (==)
9 RETURN_VALUE
>>> dis.dis('True == 1')
1 0 LOAD_GLOBAL ...
Converting between datetime, Timestamp and datetime64
...amp(ts)
datetime.datetime(2012, 12, 4, 19, 51, 25, 362455)
>>> np.__version__
'1.8.0.dev-7b75899'
The above example assumes that a naive datetime object is interpreted by np.datetime64 as time in UTC.
To convert datetime to np.datetime64 and back (numpy-1.6):
>>> np.datetime6...
Efficient way to apply multiple filters to pandas DataFrame or Series
...turn op(x[col],n)
In [15]: def f(x, *b):
return x[(np.logical_and(*b))]
In [16]: b1 = b(df, 'col1', ge, 1)
In [17]: b2 = b(df, 'col1', le, 1)
In [18]: f(df, b1, b2)
Out[18]:
col1 col2
1 1 11
Update: pandas 0.13 has a query method for these kind of use cases, assuming c...
Assigning a variable NaN in python without numpy
...e 1, in <module>
File "C:\Python35\lib\fractions.py", line 146, in __new__
numerator)
ValueError: Invalid literal for Fraction: 'nan'
>>>
>>> Fraction(float('nan'))
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "C:\Python35\...
Find out time it took for a python script to complete execution
...test function"
L = []
for i in range(100):
L.append(i)
if __name__=='__main__':
from timeit import Timer
t = Timer("test()", "from __main__ import test")
print t.timeit()
Then to convert to minutes, you can simply divide by 60. If you want the script runtime in an easi...
Read-only and non-computed variable properties in Swift
...property which returns that property:
public class Clock {
private var _hours = 0
public var hours: UInt {
return _hours
}
}
But this can be achieved in a different, shorter way, as stated in the section "Access Control" of the "The Swift Programming Language" book:
public class Clo...
How to do Base64 encoding in node.js?
...wered May 31 '11 at 2:46
onteria_onteria_
57.1k66 gold badges6363 silver badges6060 bronze badges
...
How do I find the location of my Python site-packages directory?
...ysconfig module instead:
python3 -c 'import sysconfig; print(sysconfig.get_paths()["purelib"])'
The per user site-packages directory (PEP 370) is where Python installs your local packages:
python -m site --user-site
If this points to a non-existing directory check the exit status of Python and ...
Running unittest with typical test directory structure
...e TestLoader class).
For example for a directory structure like this:
new_project
├── antigravity.py
└── test_antigravity.py
You can just run:
$ cd new_project
$ python -m unittest test_antigravity
For a directory structure like yours:
new_project
├── antigravity
│ ...
How to convert a scala.List to a java.util.List?
...1,2,3))
From Scala 2.8 onwards:
import scala.collection.JavaConversions._
import scala.collection.mutable.ListBuffer
asList(ListBuffer(List(1,2,3): _*))
val x: java.util.List[Int] = ListBuffer(List(1,2,3): _*)
However, asList in that example is not necessary if the type expected is a Java List,...