大约有 47,000 项符合查询结果（耗时：0.0443秒） [XML]
[] and {} vs list() and dict(), which is better?
...s/dicts:
>>> from timeit import timeit
>>> timeit("[]")
0.040084982867934334
>>> timeit("list()")
0.17704233359267718
>>> timeit("{}")
0.033620194745424214
>>> timeit("dict()")
0.1821558326547077
and for non-empty:
>>> timeit("[1,2,3]")
0.243...
How to identify numpy types in python?
... numpy enough type?
– panda-34
Mar 10 '16 at 13:02
If you want anything in numpy.* you just walk the parent package of...
Detail change after Git pull
...
209
Suppose you're pulling to master. You can refer to the previous position of master by master@{1...
How to initialize all members of an array to the same value?
...
Unless that value is 0 (in which case you can omit some part of the initializer
and the corresponding elements will be initialized to 0), there's no easy way.
Don't overlook the obvious solution, though:
int myArray[10] = { 5, 5, 5, 5, 5, 5, 5,...
Returning value from called function in a shell script
... echo >&2 "successfully acquired lock: $lockdir"
retval=0
else
echo >&2 "cannot acquire lock, giving up on $lockdir"
retval=1
fi
return "$retval"
}
testlock
retval=$?
if [ "$retval" == 0 ]
then
echo "directory not created"
else
echo ...
How to create NS_OPTIONS-style bitmask enumerations in Swift?
...
Swift 3.0
Almost identical to Swift 2.0. OptionSetType was renamed to OptionSet and enums are written lower case by convention.
struct MyOptions : OptionSet {
let rawValue: Int
static let firstOption = MyOptions(rawValue:...
Efficient way to insert a number into a sorted array of numbers?
...
Just as a single data point, for kicks I tested this out inserting 1000 random elements into an array of 100,000 pre-sorted numbers using the two methods using Chrome on Windows 7:
First Method:
~54 milliseconds
Second Method:
~57 seconds
So, at least on this setup, the native method doesn...
How can I update the current line in a C# Windows Console App?
...
805
If you print only "\r" to the console the cursor goes back to the beginning of the current line...
Adding an arbitrary line to a matplotlib plot in ipython notebook
...as np
import matplotlib.pyplot as plt
np.random.seed(5)
x = np.arange(1, 101)
y = 20 + 3 * x + np.random.normal(0, 60, 100)
plt.plot(x, y, "o")
# draw vertical line from (70,100) to (70, 250)
plt.plot([70, 70], [100, 250], 'k-', lw=2)
# draw diagonal line from (70, 90) to (90, 200)
plt.plot([70,...
Get loop count inside a Python FOR loop
...
605
The pythonic way is to use enumerate:
for idx,item in enumerate(list):
...