大约有 40,000 项符合查询结果（耗时：0.0479秒） [XML]
Set default CRAN mirror permanent in R
...?Startup:
The
path of this file is taken from the value of the R_PROFILE
environment variable (after tilde expansion). If this variable is
unset, the default is R_HOME/etc/Rprofile.site, which is used if
it exists (which it does not in a 'factory-fresh' installation)...
Secret copy to clipboard JavaScript function in Chrome and Firefox?
...learConsoleMessages();
}
> copy
function (object)
{
if (injectedScript._type(object) === "node")
object = object.outerHTML;
InjectedScriptHost.copyText(object);
}
While the Firebug source also defines a list of functions:
this.clear = function() // no web page interaction
{
Firebug.Cons...
JavaScript equivalent to printf/String.Format
...
@Raphael_ and @rescdsk: .. also works: 33333..toExponential(2);
– Peter Jaric
May 7 '13 at 8:12
...
How to print number with commas as thousands separators?
... For Python ≥3.6
Locale aware
import locale
locale.setlocale(locale.LC_ALL, '') # Use '' for auto, or force e.g. to 'en_US.UTF-8'
'{:n}'.format(value) # For Python ≥2.7
f'{value:n}' # For Python ≥3.6
Reference
Per Format Specification Mini-Language,
The ',' option signals the use...
How to sort an array of integers correctly
... answered Nov 17 '18 at 21:01
dy_dy_
4,12744 gold badges2020 silver badges2828 bronze badges
...
Can table columns with a Foreign Key be NULL?
...NGINE=INNODB;
CREATE TABLE child (id INT NULL,
parent_id INT NULL,
FOREIGN KEY (parent_id) REFERENCES parent(id)
) ENGINE=INNODB;
INSERT INTO child (id, parent_id) VALUES (1, NULL);
-- Query OK, 1 row affected (0.01 sec)
INSERT INTO child (id, parent_id)...
validation custom message for rails 3
...ant to remove the field title from the message you should use this on your _form.htmk.erb view:
As you can see inside this view:
<ul>
<% @article.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
Replace it by:
<ul>
...
Finding duplicate values in a SQL table
...aggregated columns in the GROUP BY.
MySQL is unpredictable and you need sql_mode=only_full_group_by:
GROUP BY lname ORDER BY showing wrong results;
Which is the least expensive aggregate function in the absence of ANY() (see comments in accepted answer).
Oracle isn't mainstream enough (warning: h...
ImageConvertor 扩展：免费图像转换器，支持JPG/PNG/WEBP格式转换和图像处...
...路径 = 文件选择器.路径
设置 旋转后路径 = "/sdcard/rotated_image.jpg"
调用 ImageConvertor1.Rotate 原图路径 旋转后路径 90
图像缩放
当 缩放按钮.被点击
设置 原图路径 = "/sdcard/large_image.jpg"
设置 缩放后路径 = "/sdca...
How to get all possible combinations of a list’s elements?
...nd iterate through that:
from itertools import chain, combinations
def all_subsets(ss):
return chain(*map(lambda x: combinations(ss, x), range(0, len(ss)+1)))
for subset in all_subsets(stuff):
print(subset)
share
...