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How does collections.defaultdict work?
... as default_factory, any unknown key will return 0 by default.
Now as the string is passed in the loop, it will increase the count of those alphabets in d.
>>> s = 'mississippi'
>>> d = defaultdict(int)
>>> d.default_factory
<type 'int'>
>>> for k in s:
.....
Can I replace groups in Java regex?
...(...). I'm assuming you wanted to replace the first group with the literal string "number" and the second group with the value of the first group.
Pattern p = Pattern.compile("(\\d)(.*)(\\d)");
String input = "6 example input 4";
Matcher m = p.matcher(input);
if (m.find()) {
// replace first nu...
How can you get the Manifest Version number from the App's (Layout) XML variables?
...de. What I have been doing up until now is to link the version number in a String XML file to the manifest (@string/Version). What I would like to do is to do it the other way around, link a string XML variable to the version in the manifest. The reason? I'd like to only have to change the version n...
JSONP with ASP.NET Web API
..., and now I am trying to consume it using JQuery. I can get back the JSON string using Fiddler, and it seems to be ok, but because the service exists on a separate site, trying to call it with JQuery errors with the "Not Allowed". So, this is clearly a case where I need to use JSONP.
...
Calculate distance between two latitude-longitude points? (Haversine formula)
...it's pretty much the same as the values obtained from Apple's Map app :-)
Extra update:
If you are using iOS4 or later then Apple provide some methods to do this so the same functionality would be achieved with:
-(double)kilometresBetweenPlace1:(CLLocationCoordinate2D) place1 andPlace2:(CLLocatio...
Curly braces in string in PHP
What is the meaning of { } (curly braces) in string literals in PHP?
5 Answers
5
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How to JSON serialize sets?
...
JSON notation has only a handful of native datatypes (objects, arrays, strings, numbers, booleans, and null), so anything serialized in JSON needs to be expressed as one of these types.
As shown in the json module docs, this conversion can be done automatically by a JSONEncoder and JSONDecoder,...
Update MongoDB field using value of another field
....0
The way we do this is by $projecting our documents and use the $concat string aggregation operator to return the concatenated string.
we From there, you then iterate the cursor and use the $set update operator to add the new field to your documents using bulk operations for maximum efficiency.
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Is modern C++ becoming more prevalent? [closed]
...ated C++ and Stroustrup's new textbook. So we don't learn char* then std::strings.
It's an interesting lesson in how long it takes for "legacy" methods to be replaced, especially when they have a track record of effectiveness.
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Collections.emptyMap() vs new HashMap()
...e this, and does not allow null references:
public ResultSet executeQuery(String query, Map<String, Object> queryParameters);
If you have a query that doesn't take any parameters, it's certainly a bit wasteful to create a HashMap, which involves allocating an array, when you could just pass...