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Mathematical functions in Swift
...an import only Darwin.
import Darwin
If you want mathematical functions and other standard classes and functions. You can import Foundation.
import Foundation
If you want everything and also classes for user interface, it depends if your playground is for OS X or iOS.
For OS X, you need impor...
How can I get the current network interface throughput statistics on Linux/UNIX? [closed]
Tools such as MRTG provide network throughput / bandwidth graphs for the current network utilisation on specific interfaces, such as eth0. How can I return that information at the command line on Linux/UNIX?
...
Is it possible to install iOS 6 SDK on Xcode 5?
...awhile since we updated; but they still accepted it after iOS 6 came out), and I currently build 10.5 apps with Xcode 5.
See How to point Xcode to an old SDK so it can be used as a "Base SDK"? for details on how to set it up. You can use my fix-xcode
script to link everything for you every time yo...
What is an idempotent operation?
...g that x in the mathematical definition represents the state of an object, and f is an operation that may mutate that object. For example, consider the Python set and its discard method. The discard method removes an element from a set, and does nothing if the element does not exist. So:
my_set.dis...
How do I integrate Ajax with Django applications?
I am new to Django and pretty new to Ajax. I am working on a project where I need to integrate the two. I believe that I understand the principles behind them both, but have not found a good explanation of the two together.
...
How to optimize for-comprehensions and loops in Scala?
...imizer can eliminate the foreach but cannot yet eliminate the throw/catch. And throw/catch is expensive. But since such nested returns are rare in Scala programs, the optimizer did not yet address this case. There is work going on to improve the optimizer which hopefully will solve this issue soon.
...
Can someone explain the traverse function in Haskell?
I am trying and failing to grok the traverse function from Data.Traversable . I am unable to see its point. Since I come from an imperative background, can someone please explain it to me in terms of an imperative loop? Pseudo-code would be much appreciated. Thanks.
...
python date of the previous month
...
datetime and the datetime.timedelta classes are your friend.
find today.
use that to find the first day of this month.
use timedelta to backup a single day, to the last day of the previous month.
print the YYYYMM string you're looki...
Git diff against a stash
...h show -p stash@{1}
From the git stash manpages:
By default, the command shows the diffstat, but it will accept any
format known to git diff (e.g., git stash show -p stash@{1} to view
the second most recent stash in patch form).
...
Switch on ranges of integers in JavaScript [duplicate]
... than five");
break;
case (x < 9):
alert("between 5 and 8");
break;
case (x < 12):
alert("between 9 and 11");
break;
default:
alert("none");
break;
}
...