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Ways to implement data versioning in MongoDB
...DB is designed for exactly this type of change (add new property / push to array).
– Gates VP
Nov 17 '10 at 5:59
2
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How can I use threading in Python?
...Pool as ThreadPool
pool = ThreadPool(4)
results = pool.map(my_function, my_array)
Which is the multithreaded version of:
results = []
for item in my_array:
results.append(my_function(item))
Description
Map is a cool little function, and the key to easily injecting parallelism into your Pytho...
Get property value from string using reflection
...y jheddings. I would like to improve it allowing referencing of aggregated arrays or collections of objects, so that propertyName could be property1.property2[X].property3:
public static object GetPropertyValue(object srcobj, string propertyName)
{
if (srcobj == null)
re...
Conveniently map between enum and int / String
...
Using the values() array will only work if all your values are 0 indexed for their id and are declared in order. (I tested this to verify that if you declare FOO(0), BAR(2), BAZ(1); that values[1] == BAR and values[2] == BAZ despite the ids pas...
Thread-safe List property
...er, a workaround could be to use ConcurrentDictionary with integer TKey as array index and TValue as array value. This is recommended way of replacing list in Pluralsight's C# Concurrent Collections course. ConcurrentDictionary solves both problems mentioned above: index accessing and ordering (we c...
How does collections.defaultdict work?
...llections import defaultdict
# Time complexity O(n^2)
def delete_nth_naive(array, n):
ans = []
for num in array:
if ans.count(num) < n:
ans.append(num)
return ans
# Time Complexity O(n), using hash tables.
def delete_nth(array,n):
result = []
counts = defa...
Plot two histograms on single chart with matplotlib
...ogram_demo_multihist.html
EDIT [2018/03/16]: Updated to allow plotting of arrays of different sizes, as suggested by @stochastic_zeitgeist
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Repeat String - Javascript
...is old and and not terribly practical - it's just "clever" because it uses Array stuff to get
String things done. When I wrote "less process" I definitely meant
"less code" because, as others have noted in subsequent answers, it
performs like a pig. So don't use it if speed matters to you.
I...
How to make ng-repeat filter out duplicate results
...n the collection and which field
// should be unique
// We assume an array of objects here
// NOTE: We are skipping any object which
// contains a duplicated value for that
// particular key. Make sure this is what
// you want!
return function (arr, targetField) {
var val...
Are there strongly-typed collections in Objective-C?
...ve-C, they will generate compiler warnings if there is a type mismatch.
NSArray<NSString*>* arr = @[@"str"];
NSString* string = [arr objectAtIndex:0];
NSNumber* number = [arr objectAtIndex:0]; // Warning: Incompatible pointer types initializing 'NSNumber *' with an expression of type 'NSStri...