大约有 13,922 项符合查询结果（耗时：0.0211秒） [XML]
Most efficient way to reverse a numpy array
...ersed_arr)
do_something_else(arr)
look_at(reversed_arr)
I'm not a numpy expert, but this seems like it would be the fastest way to do things in numpy. If this is what you are already doing, I don't think you can improve on it.
P.S. Great discussion of numpy views here:
View onto a numpy array?
...
How to change the type of a field?
...g).
So simply load the document from the DB, perform the cast (new String(x)) and then save the document again.
If you need to do this programmatically and entirely from the shell, you can use the find(...).forEach(function(x) {}) syntax.
In response to the second comment below. Change the fiel...
Python, compute list difference
...ase on lists with ~6000 strings each showed that this method was almost 100x faster than list comprehensions.
– perrygeo
Feb 1 '14 at 17:01
15
...
What is the printf format specifier for bool?
...t when passed down to printf()'s variadic arguments, you can use %d:
bool x = true;
printf("%d\n", x); // prints 1
But why not:
printf(x ? "true" : "false");
or, better:
printf("%s", x ? "true" : "false");
or, even better:
fputs(x ? "true" : "false", stdout);
instead?
...
Why are empty strings returned in split() results?
...returned in split() results, you may want to look at the filter function.
Example:
f = filter(None, '/segment/segment/'.split('/'))
s_all = list(f)
returns
['segment', 'segment']
share
|
improve t...
What does ~~ (“double tilde”) do in Javascript?
...strings, and the result is a number.
In other words, it yields:
function(x) {
if(x < 0) return Math.ceil(x);
else return Math.floor(x);
}
only if x is between -(231) and 231 - 1. Otherwise, overflow will occur and the number will "wrap around".
This may be considered useful to convert a ...
How to merge a list of lists with same type of items to a single list of items?
...
Use the SelectMany extension method
list = listOfList.SelectMany(x => x).ToList();
share
|
improve this answer
|
f...
Extracting just Month and Year separately from Pandas Datetime column
...ng year and month separately you can do this:
df['year'] = pd.DatetimeIndex(df['ArrivalDate']).year
df['month'] = pd.DatetimeIndex(df['ArrivalDate']).month
or...
df['year'] = df['ArrivalDate'].dt.year
df['month'] = df['ArrivalDate'].dt.month
Then you can combine them or work with them just as ...
How to print a number with commas as thousands separators in JavaScript
...print an integer in JavaScript with commas as thousands separators. For example, I want to show the number 1234567 as "1,234,567". How would I go about doing this?
...
What is the difference between i++ and ++i?
...es the variable is incremented, but if you were to take the value of both expressions in exactly the same cases, the result will differ.
share
|
improve this answer
|
follow
...