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Python concatenate text files
...new file. I could open each file by f = open(...) , read line by line by calling f.readline() , and write each line into that new file. It doesn't seem very "elegant" to me, especially the part where I have to read//write line by line.
...
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...
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...
How to delete an object by id with entity framework
...
The same as @Nix with a small change to be strongly typed:
If you don't want to query for it just create an entity, and then delete it.
Customer customer = new Customer () { Id = id };
context.Customers.Attach(custome...
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...
Call a “local” function within module.exports from another function in module.exports?
How do you call a function from within another function in a module.exports declaration?
8 Answers
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Real world use cases of bitwise operators [closed]
...checksums, parity, stop bits, flow control algorithms, and so on, which usually depend on the logic values of individual bytes as opposed to numeric values, since the medium may only be capable of transmitting one bit at a time.
Compression, Encryption
Both of these are heavily dependent on bitwise ...
Creating Threads in python
...see how:
from threading import Thread
from time import sleep
def threaded_function(arg):
for i in range(arg):
print("running")
sleep(1)
if __name__ == "__main__":
thread = Thread(target = threaded_function, args = (10, ))
thread.start()
thread.join()
print("th...
Resharper- Find all unused classes
...g the "Find Usages" option. Is there any way I can see or get the list of all the unused classes or files in my project ?
...
javac is not recognized as an internal or external command, operable program or batch file [closed]
...nal or external command... error message.
In a nutshell, you have not installed Java correctly. Finalizing the installation of Java on Windows requires some manual steps. You must always perform these steps after installing Java, including after upgrading the JDK.
Environment variables and PATH
(...