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How to clear the interpreter console?
Like most Python developers, I typically keep a console window open with the Python interpreter running to test commands, dir() stuff, help() stuff , etc.
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Getting a map() to return a list in Python 3.x
...ases, this ends up saving memory, and should make things go faster.
If all you're going to do is iterate over this list eventually, there's no need to even convert it to a list, because you can still iterate over the map object like so:
# Prints "ABCD"
for ch in map(chr,[65,66,67,68]):
prin...
Using OR in SQLAlchemy
...
From the tutorial:
from sqlalchemy import or_
filter(or_(User.name == 'ed', User.name == 'wendy'))
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Multiple columns index when using the declarative ORM extension of sqlalchemy
...e just Column objects, index=True flag works normally:
class A(Base):
__tablename__ = 'table_A'
id = Column(Integer, primary_key=True)
a = Column(String(32), index=True)
b = Column(String(32), index=True)
if you'd like a composite index, again Table is present here as usual you ju...
Iterate two Lists or Arrays with one ForEach statement in C#
... Did not know anything about those Zip operations, I'll make a small research on that topic. Thanks!
– Hugo
Dec 23 '09 at 23:02
4
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Apply multiple functions to multiple groupby columns
...ion.
I recommend making a single custom function that returns a Series of all the aggregations. Use the Series index as labels for the new columns:
def f(x):
d = {}
d['a_sum'] = x['a'].sum()
d['a_max'] = x['a'].max()
d['b_mean'] = x['b'].mean()
d['c_d_prodsum'] = (x['c'] * x['d...
In Django, how does one filter a QuerySet with dynamic field lookups?
...a custom ModelField/FormField/WidgetField that implemented the behavior to allow the user to, on the GUI side, basically "build" a query, never seeing the actual text, but using an interface to do so. Sounds like a neat project...
– T. Stone
Sep 23 '09 at 20:2...
How to get a variable name as a string in PHP?
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Actually now that I've tested my code, my code always returned 'var' because it's being used in the function. When I use $GLOBALS instead, it returns the correct variable name for some reason. So I'll change the above code to use...
MDI CDockablePane使用总结 - C/C++ - 清泛网 - 专注C/C++及内核技术
...架类的头文件中定义一个CDockablePane的数组
CDockablePane m_Panes[5];//一个CDockablePane的数组
2. CFrameWndEx:: OnCreate() 在Create函数中自动生成了以下代码，对MFC比较熟悉的这里就不讲了：
CMFCPopupMenu::SetForceMenuFocus(FALSE);
InitUserToolbars(N...
C/C++获取Windows的CPU、内存、硬盘使用率 - C/C++ - 清泛网 - 专注C/C++及内核技术
...率1.获取Windows系统内存使用率 Win 内存 使用率 DWORD getWin_MemUsage(){MEMORYSTATUS ms;::GlobalMemoryStatus(&ms);return ms.d...1.获取Windows系统内存使用率
//Win 内存 使用率
DWORD getWin_MemUsage()
{
MEMORYSTATUS ms;
::GlobalMemoryStatus(&ms);
return ms.dwMe...