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Simple explanation of MapReduce?
...e reduced to a scalar value.
So if you think of it like a SQL statement
SELECT SUM(salary)
FROM employees
WHERE salary > 1000
GROUP by deptname
We can use map to get our subset of employees with salary > 1000
which map emits to the barrier into group size buckets.
Reduce will sum each of...
What is the difference between “JPG” / “JPEG” / “PNG” / “BMP” / “GIF” / “TIFF” Image?
...ow demonstrate the noticeable artifacting of lossy compression algorithms; select the thumbnail image to view the full size version.
Each format is different as described below:
JPEG
JPEG (Joint Photographic Experts Group) files are (in most cases) a lossy format; the DOS filename extension is JPG...
What is a Portable Class Library?
...g screenshots and detailed matrices showing available features across your selections if you're into that sort of thing.
See Portable Library Tools anouncement blog post, which starts:-
The Portable Library Tools CTP adds a new "Portable Class Library" project template to Visual Studio that c...
How to implement a rule engine?
..."Contains", "C#" )
};
// compile the rules once
var compiledRules = rules.Select(r => CompileRule(r)).ToList();
public bool MatchesAllRules(User user)
{
return compiledRules.All(rule => rule(user));
}
Here is the implementation of BuildExpr:
Expression BuildExpr(Rule r, ParameterExpress...
What are the most widely used C++ vector/matrix math/linear algebra libraries, and their cost and be
...s criteria, but if maturity were the only metric, I imagine you would have selected a BLAS or LAPACK based option.
– Catskul
Sep 9 '09 at 17:54
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base64 encoded images in email signatures
...tlook. I then used the signature editors "replace image" functionality to select a local file (instead of the base64 encoded image I had manually included). This seems to do what you mean. Thanks for sticking with me.
– Devil's Advocate
Dec 2 '16 at 16:30
...
What is polymorphism, what is it for, and how is it used?
...g different courses of action, you create interchangeable objects that you select based on your needs. That is the basic goal of polymorphism.
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Filter rows which contain a certain string
... @MySchizoBuddy: If the column name contains white space, you can select the variable using backticks. Modifying the example above: mtcars$`my type` <- rownames(mtcars) and then mtcars %>% filter(grepl('Toyota|Mazda', `my type`))
– alex23lemm
Ju...
Algorithm to generate a crossword
...the previous steps can just be done once.
First step of the algorithm is select an empty wordslot (grid word) at random and fill it with a candidate word from its associated wordlist (randomization enables to produce different solutons in consecutive executions of the algorithm) ( complexity O(1)...
ServiceStack vs ASP.Net Web API [closed]
...solveService<T>() method which returns an auto-wired instance of the selected service as seen in the Nortwind CustomerDetails Service example:
var ordersService = base.ResolveService<OrdersService>();
var ordersResponse = (OrdersResponse)ordersService.Get(
new Orders { CustomerId = ...