大约有 40,000 项符合查询结果（耗时：0.0410秒） [XML]
What is the use of join() in Python threading?
... @Aviator45003: Yes, by using the timeout argument like: demon_thread.join(0.0), join() is by default blocking without regard to the daemonized attribute. But joining a demonized thread opens most likely a whole can of trouble! I'm now considering to remove the join() call in my little ...
Read Excel File in Python
...
This is one approach:
from xlrd import open_workbook
class Arm(object):
def __init__(self, id, dsp_name, dsp_code, hub_code, pin_code, pptl):
self.id = id
self.dsp_name = dsp_name
self.dsp_code = dsp_code
self.hub_code = hub_code
...
How to update PATH variable permanently from Windows command line?
...mmatically add or modify system environment variables, add them to the HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment registry key, then broadcast a WM_SETTINGCHANGE message with lParam set to the string "Environment". This allows applications, such as the shell, to ...
Extracting bits with a single multiplication
...and, namely SMT-LIB 2 input:
(set-logic BV)
(declare-const mask (_ BitVec 64))
(declare-const multiplicand (_ BitVec 64))
(assert
(forall ((x (_ BitVec 64)))
(let ((y (bvmul (bvand mask x) multiplicand)))
(and
(= ((_ extract 63 63) x) ((_ extract 63 63) y))
(= ...
What's the best UI for entering date of birth? [closed]
...birthdate.
A text box with an example is clear, quick and easy to enter:
_______
|_______| (example: 31/3/1970)
This should support flexible formatting such as 1/1/1970 or 20/07/70.
If you have to support different cultures with different date conventions (e.g. US and UK) then this could be err...
do N times (declarative syntax)
...s 2017, you may use ES6:
[1,2,3].forEach(i => Array(i).fill(i).forEach(_ => {
something()
}))
or in good old ES5:
[1,2,3].forEach(function(i) {
Array(i).fill(i).forEach(function() {
something()
})
}))
In both cases, the outpout will be
The outpout will be
something
somethin...
Getter and Setter declaration in .NET [duplicate]
...ed property. When the need arises you can expand your property to:
string _myProperty;
public string MyProperty
{
get { return _myProperty; }
set { _myProperty = value; }
}
Now you can add code that validates the value in your setter:
set
{
if (string.IsNullOrWhiteSpace(value))
...
How to put multiple statements in one line?
...e generally discouraged.
Yes:
if foo == 'blah':
do_blah_thing()
do_one()
do_two()
do_three()
Rather not:
if foo == 'blah': do_blah_thing()
do_one(); do_two(); do_three()
Here is a sample comprehension to make the distinction:
>>...
What is a proper naming convention for MySQL FKs?
...ue name automatically.
In any case, this is the convention that I use:
fk_[referencing table name]_[referenced table name]_[referencing field name]
Example:
CREATE TABLE users(
user_id int,
name varchar(100)
);
CREATE TABLE messages(
message_id int,
user_id int
);
...
rgdal package installation
...file update
Then, when you get an error such as :
configure: error: proj_api.h not found in standard or given locations.
You can use the following command to find which package you must install to get the missing file :
$ apt-file search proj_api.h
libproj-dev: /usr/include/proj_api.h
...