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How can I make pandas dataframe column headers all lowercase?
...da CAN 2002 1.56932 9.572999e+05
2 Canada CAN 2003 1.40105 1.016902e+06
In [64]: df.columns = df.columns.str.lower()
In [65]: df
Out[65]:
country country isocode year xrat tcgdp
0 Canada CAN 2001 1.54876 9.249094e+05
1 Canada ...
_DEBUG vs NDEBUG
... is a standard macro with the semantic "Not Debug" for C89, C99, C++98, C++2003, C++2011, C++2014 standards. There are no _DEBUG macros in the standards.
C++2003 standard send the reader at "page 326" at "17.4.2.1 Headers"
to standard C.
That NDEBUG is similar as This is the same as the Standa...
multiprocessing: How do I share a dict among multiple processes?
...t a copy of the main process's memory" means.
– Itsme2003
Oct 7 '18 at 15:10
@Itsme2003 by default a spawned process h...
How to define two fields “unique” as couple
...
@Greg - According to the ANSI standard SQL:2003 (and previous ones as well), a UNIQUE constraint should disallow duplicate non-NULL values, but allow multiple NULL values (see draft wiscorp.com/sql_2003_standard.zip, Framework, p. 22). If you want your unique constrai...
Targeting .NET Framework 4.5 via Visual Studio 2010
...d to a specific .NET framework. (VS2008 is .NET 3.5, VS2005 is .NET 2.0, VS2003 is .NET1.1) Visual Studio 2010 and beyond allow for targeting of prior framework versions but cannot be used for future releases. You must use Visual Studio 2012 in order to utilize .NET 4.5.
...
Escaping keyword-like column names in Postgres
...ide you have to build the insert statement with delimited identifiers.
SQL 2003 specifies that a delimited identifier should be quoted with double quotes " and if a double quote occurs in the identifier, the double quote must be duplicated. See the BNF:
https://ronsavage.github.io/SQL/sql-2003-2.bn...
How expensive is the lock statement?
...ead the linked article to the end. article
The author of the article from 2003 article was measuring on Dual Core machine only and in the first measuring case, he measured locking with a single thread only and the result was about 50ns per lock access.
It says nothing about a lock in the concurren...
Using Excel OleDb to get sheet names IN SHEET ORDER
...et name for Excel 2007,following code will be applicable for both Excel(97-2003) and Excel 2007 too:
public List<string> ListSheetInExcel(string filePath)
{
OleDbConnectionStringBuilder sbConnection = new OleDbConnectionStringBuilder();
String strExtendedProperties = String.Empty;
sb...
Is there an equivalent of 'which' on the Windows command line?
...
Windows Server 2003 and later (i.e. anything after Windows XP 32 bit) provide the where.exe program which does some of what which does, though it matches all types of files, not just executable commands. (It does not match built-in shell c...
企业级负载平衡简介 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...000000个会话。这些会话会占用负载平衡服务器的很大部分资源。而且在负载高峰期，其所消耗的资源可能会成倍地增长，会向服务器施加更多的压力。
但是将会话持续时间设置得比较短则更为麻烦。这会导致用户和负载平衡服...