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Ruby: Easiest Way to Filter Hash Keys?
...with just the choices in it.
choices = params.select { |key, value| key.to_s.match(/^choice\d+/) }
or you can use delete_if and modify the existing Hash e.g.
params.delete_if { |key, value| !key.to_s.match(/choice\d+/) }
or if it is just the keys and not the values you want then you can do:
p...
Are there benefits of passing by pointer over passing by reference in C++?
...ect", then use a pointer instead of a reference.
Also, passing by pointer allows you to explicitly see at the call site whether the object is passed by value or by reference:
// Is mySprite passed by value or by reference? You can't tell
// without looking at the definition of func()
func(mySpri...
Error-Handling in Swift-Language
...ragon
Note: there is no specification for type of error the function actually can throw. This declaration simply states that the function can throw an instance of any type implementing ErrorType or is not throwing at all.
2. Invoking function that may throw errors
In order to invoke function you...
How do I write JSON data to a file?
... codecs.getwriter('utf-8')(f), ensure_ascii=False)
The codecs.getwriter call is redundant in Python 3 but required for Python 2
Readability and size:
The use of ensure_ascii=False gives better readability and smaller size:
>>> json.dumps({'price': '€10'})
'{"price": "\\u20ac10"}'
&...
How to pass arguments to addEventListener listener function?
...you have more code that operates on the same someVar variable next to the call to addEventListener)
var someVar;
someVar = some_other_function();
alert(someVar);
someObj.addEventListener("click", function(){
some_function(someVar);
}, false);
...
How to resize an image with OpenCV2.0 and Python2.6
...ll resize the image to have 100 cols (width) and 50 rows (height):
resized_image = cv2.resize(image, (100, 50))
Another option is to use scipy module, by using:
small = scipy.misc.imresize(image, 0.5)
There are obviously more options you can read in the documentation of those functions (cv2.r...
How do I create a new Swift project without using Storyboards?
Creating a new project in XCode 6 doesn't allow to disable Storyboards. You can only select Swift or Objective-C and to use or not Core Data.
...
How to provide different Android app icons for different gradle buildTypes?
...
Figured it out. What you need to do is create a separate src folder called debug that holds the different icons. For example, if your project layout is as follows, and your launcher icon is called ic_launcher.png:
[Project Root]
-[Module]
-src
-main
-res
-drawabl...
Is it better to call ToList() or ToArray() in LINQ queries?
...the case where I want to eval a query right where I declare it. This is usually because I need to iterate over it multiple times and it is expensive to compute. For example:
...
Google Authenticator implementation in Python
...m/tadeck/onetimepass).
import hmac, base64, struct, hashlib, time
def get_hotp_token(secret, intervals_no):
key = base64.b32decode(secret, True)
msg = struct.pack(">Q", intervals_no)
h = hmac.new(key, msg, hashlib.sha1).digest()
o = ord(h[19]) & 15
h = (struct.unpack("&g...