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Getting Django admin url for an object
...o 1.0 there was an easy way to get the admin url of an object, and I had written a small filter that I'd use like this: <a href="{{ object|admin_url }}" .... > ... </a>
...
Checking if a string can be converted to float in Python
.....
try:
float(element)
except ValueError:
print "Not a float"
..it's simple, and it works
Another option would be a regular expression:
import re
if re.match(r'^-?\d+(?:\.\d+)?$', element) is None:
print "Not float"
...
Undefined symbols for architecture i386: _OBJC_CLASS_$_SKPSMTPMessage", referenced from: error
...hases" tab of your target. Normally Xcode does this for you, but sometimes it loses the plot and you need to add the .m file manually.
To do this:
TargetSettings -> Build Phases -> Compile Sources -> add your .m class ->Build and Run
...
Is “argv[0] = name-of-executable” an accepted standard or just a common convention?
...r if the program name is not available from the host environment.
So no, it's only the program name if that name is available. And it "represents" the program name, not necessarily is the program name. The section before that states:
If the value of argc is greater than zero, the array members...
Mediator Vs Observer Object-Oriented Design Patterns
...many dependency between objects so that when one object changes state, all its dependents are notified and updated automatically.
The Mediator pattern:
Define an object that encapsulates how a set of objects interact. Mediator promotes loose coupling by keeping objects from referring to each other...
Oracle “(+)” Operator
...table references) didn't standardize OUTER joins.
The query would be re-written in ANSI-92 syntax as:
SELECT ...
FROM a
LEFT JOIN b ON b.id = a.id
This link is pretty good at explaining the difference between JOINs.
It should also be noted that even though the (+) works, Oracle recomm...
Flatten nested dictionaries, compressing keys
...ay you would flatten a nested list, you just have to do the extra work for iterating the dict by key/value, creating new keys for your new dictionary and creating the dictionary at final step.
import collections
def flatten(d, parent_key='', sep='_'):
items = []
for k, v in d.items():
...
Why is SQL Server 2008 Management Studio Intellisense not working?
I'm being driven to insanity trying to figure out why Intellisense just fails to work at all. The server I'm using is local and is 2008, the database is set to 2008 compatibility, Intellisense is on in every menu I can find, and yet no member list will pop up even with a CTRL-J.
...
windows异常处理 __try __except - C/C++ - 清泛网 - 专注C/C++及内核技术
windows异常处理 __try __excepttry-except用法 try except是windows 系统独有的异常处理模型，windows的异常处理模式，称为SEH( structured exception handling ...try-except用法
try except是windows 系统独有的异常处理模型，windows的异常处理模式，...
Logical operators for boolean indexing in Pandas
I'm working with boolean index in Pandas.
The question is why the statement:
3 Answers
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