大约有 40,000 项符合查询结果(耗时:0.0331秒) [XML]
Run a Docker image as a container
...s something to run. You could replace that with a program that you've installed. /bin/bash is just a handy shell that's already installed.
– Ryan Shillington
Feb 9 '17 at 15:11
...
Is there a Python Library that contains a list of all the ascii characters?
...>> string.ascii_uppercase
'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
If you want all printable characters:
>>> string.printable
'0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!"#$%&\'()*+,-./:;?@[\\]^_`{|}~ \t\n\r\x0b\x0c'
...
C library function to perform sort
...
qsort() is the function you're looking for. You call it with a pointer to your array of data, the number of elements in that array, the size of each element and a comparison function.
It does its magic and your array is sorted in-place. An example follows:
#include <st...
How to check if a table exists in a given schema
... (like OIDs) gets lost in translation from the system catalogs - which actually carry all information.
System catalogs
Your question was:
How to check whether a table exists?
SELECT EXISTS (
SELECT FROM pg_catalog.pg_class c
JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHE...
How to implement the --verbose or -v option into a script?
...
def verboseprint(*args):
# Print each argument separately so caller doesn't need to
# stuff everything to be printed into a single string
for arg in args:
print arg,
print
else:
verboseprint = lambda *a: None # do-nothing function
(Yes, y...
STL中map容器使用自定义key类型报错详解 - C/C++ - 清泛网 - 专注C/C++及内核技术
...定义一个结构体来试试:[cpp]view plaincopystructa{char*pName;intm_a;} 引言
STL的map容器中,key的类型是不是随意的呢?
实践
编写测试代码
定义一个结构体来试试:
struct a
{
char* pName;
int m_a;
};
...
map<a, int> mp;
a ...
Why does Python use 'magic methods'?
...lable, an object implements a method, def __len__(self) , and then it is called when you write len(obj) .
7 Answers
...
Compelling examples of custom C++ allocators?
What are some really good reasons to ditch std::allocator in favor of a custom solution? Have you run across any situations where it was absolutely necessary for correctness, performance, scalability, etc? Any really clever examples?
...
Static methods in Python?
Is it possible to have static methods in Python which I could call without initializing a class, like:
10 Answers
...
Disable messages upon loading a package
...y R script is being used for further analysis I want to completely disable all of this output. How do I do that? Furthermore, I'd prefer to do it without having to modify ROCR at all, so that future users of this script don't have to do that either.
...
