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Is arr.__len__() the preferred way to get the length of an array in Python?
...ents could still be length-checked. This includes strings, queues, trees, etc.
The functional nature of len() also lends itself well to functional styles of programming.
lengths = map(len, list_of_containers)
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What does LINQ return when the results are empty
...mpty" IQueryable, which ToList() will correctly change to be an empty list etc.
Do be careful with some of the operators, as they will throw if you send them an empty enumerable. This can happen when you chain them together.
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How to indent a few lines in Markdown markup?
... chunk of text look like code as I'll use other formatting like bold face, etc. How to do that in Markdown?
22 Answers
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java: ArrayList - how can i check if an index exists?
...ould consider organizing it as a class to get rid of the magic numbers 3,8 etc.
Control flow using exception is bad practice.
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Scala: Abstract types vs generics
...l need to subclass Buffer—they can just use Buffer[Any], Buffer[String], etc.
If you use an abstract type, then people will be forced to create a subclass. People will need classes like AnyBuffer, StringBuffer, etc.
You need to decide which is better for your particular need.
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Dealing with “java.lang.OutOfMemoryError: PermGen space” error
...ingEnabled -XX:+CMSPermGenSweepingEnabled" - Restarted tomcat using: sudo /etc/init.d/tomcat6 start
– sami
Dec 10 '10 at 14:44
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How to use the PI constant in C++
...t take this approach, we people make mistakes, rounding, copy&pasting, etc. I think using M_PI is the right approach.
– nacho4d
Jan 21 '14 at 1:47
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Create a .csv file with values from a Python list
...l fields, only fields with quotes and seperators, only non numeric fields, etc) and how to esacpe control charecters (double quotes, or escaped strings). If your values are simple, string.join will probably be OK but if you're having to manage lots of edge cases, use the module available.
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Getting MAC Address
... iface you want the MAC for since many can exist (bluetooth, several nics, etc.).
This does the job when you know the IP of the iface you need the MAC for, using netifaces (available in PyPI):
import netifaces as nif
def mac_for_ip(ip):
'Returns a list of MACs for interfaces that have given IP...
How to group time by hour or by 10 minutes
... to group by a longer period then 60 minutes, say 720, which is half a day etc.