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Different floating point result with optimization enabled - compiler bug?
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I think this is the answer. The constant 4.55 gets converted to 4.54999999999999 which is the closest binary representation in 64 bits; multiply by 10 and round again to 64 bits and you get 45.5. If you skip the rounding step by keeping it in an 80-bit register you end up wit...
How to get first and last day of previous month (with timestamp) in SQL Server
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First Day Of Current Week.
select CONVERT(varchar,dateadd(week,datediff(week,0,getdate()),0),106)
Last Day Of Current Week.
select CONVERT(varchar,dateadd(week,datediff(week,0,getdate()),6),106)
First Day Of Last week.
select CONVERT(varchar,DATEADD(wee...
Is the Scala 2.8 collections library a case of “the longest suicide note in history”? [closed]
...then further generalized by only requiring that a function exists that can convert the result to whatever data structure the user wants:
map :: IterableLike i ⇒ (a → b) → i → ([b] → c) → c
I admit that the syntax is a bit clunkier, but the semantics are the same. Basically, it starts ...
Why does Stream not implement Iterable?
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To convert a Stream to an Iterable, you can do
Stream<X> stream = null;
Iterable<X> iterable = stream::iterator
To pass a Stream to a method that expects Iterable,
void foo(Iterable<X> iterable)
simply
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Double not (!!) operator in PHP
...It means if $row has a truthy value, it will return true, otherwise false, converting to a boolean value.
Here is example expressions to boolean conversion from php docs.
Expression Boolean
$x = ""; FALSE
$x = null; FALSE
var $x; FALSE
$x is und...
How to initialize std::vector from C-style array?
...aster than it looks.
template<typename T, size_t N>
vector<T> convert_array_to_vector(const T (&source_array)[N]) {
return vector<T>(source_array, source_array+N);
}
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Which are more performant, CTE or temporary tables?
...en with two CTEs in SQL server. It was taking 28sec.
I spent two minutes converting them to temp tables and the query took 3 seconds
I added an index to the temp table on the field it was being joined on and got it down to 2 seconds
Three minutes of work and now its running 12x faster all by rem...
Difference between string and char[] types in C++
... and certain functions may only accept a string as input, requiring you to convert the array to a string. It's better to use strings, they were made so that you don't have to use arrays. If arrays were objectively better we wouldn't have strings.
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Case objects vs Enumerations in Scala
...ceVal(character: Char, pointValue: Int) extends super.Val()
implicit def convert(value: Value) = value.asInstanceOf[ChessPieceVal]
}
The following items from the enumeration definition are not available (happens to be identical to the list for directly using the Java Enum):
3.1 - It would be...
Is multiplication and division using shift operators in C actually faster?
...upport fast multiplication (and
most didn't back then), the compiler would convert the multiplication
into the appropriate combinations of shifts and add/sub. And because it
knew the final goal, it could sometimes do so in less instructions than
when you explicitly wrote the shifts and the add/subs...