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How do you know when to use fold-left and when to use fold-right?
...ack up for large lists, while a foldLeft won't.
Example:
scala> List.range(1, 10000).foldLeft(0)(_ + _)
res1: Int = 49995000
scala> List.range(1, 10000).foldRight(0)(_ + _)
java.lang.StackOverflowError
at scala.List.foldRight(List.scala:1081)
at scala.List.foldRight(List.sc...
How to use Swift @autoclosure
...t a cooked function(or returned type) meanwhile a general closure accept a raw function
@autoclosure argument type parameter must be '()'
@autoclosure ()
@autoclosure accept any function with only appropriate returned type
Result of closure is calculated by demand
Let's take a look at examp...
How to navigate through a vector using iterators? (C++)
...ata from an input stream, or that simply generates data on the fly (e.g. a range or random number generator).
Another option using std::for_each and lambdas:
sum = 0;
std::for_each(vec.begin(), vec.end(), [&sum](int i) { sum += i; });
Since C++11 you can use auto to avoid specifying a very l...
Apply multiple functions to multiple groupby columns
... b_mean=('b', 'mean'),
c_sum=('c', 'sum'),
d_range=('d', lambda x: x.max() - x.min())
)
a_sum a_mean b_mean c_sum d_range
group
0 0.947337 0.473668 0.871939 0.838150 0.320543
1 0.6041...
Why does Go have a “goto” statement
... The referenced code is not optimized for readability. It is optimized for raw performance, using a goto that spans 22 lines within a single function. (And Thomas Ahle's proposal is even more readable to my eye.)
– joel.neely
Jun 28 '16 at 11:14
...
C++, Free-Store vs Heap
... I generally think of the heap (via maloc/free) as a sort of 'raw' material supplier. You ask for a chunk of memory you get it no frills. You have to build any structures yourself. The Free Store (new/delete) is more like a 'finished goods' supplier. You ask for an object and it gets a...
Fitting empirical distribution to theoretical ones with Scipy (Python)?
INTRODUCTION : I have a list of more than 30,000 integer values ranging from 0 to 47, inclusive, e.g. [0,0,0,0,..,1,1,1,1,...,2,2,2,2,...,47,47,47,...] sampled from some continuous distribution. The values in the list are not necessarily in order, but order doesn't matter for this problem.
...
Do I cast the result of malloc?
...e (alleged) desired type right next to the arithmetic you're doing for the raw size of that variable. I bet you could do an SO study that shows that malloc() bugs are caught much faster when there's a cast. As with assertions, annotations that reveal intent decrease bugs.
Repeating yourself in a wa...
Spring RestTemplate - how to enable full debugging/logging of requests/responses?
...sh The content is probably gzip encoded which is why you're not seeing the raw text.
– Matthew Buckett
Jan 21 '19 at 11:33
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show 2 more com...
Unicode equivalents for \w and \b in Java regular expressions?
...\w))
with the \w defined in the appropriate way.
(You might think it strange that the A and C components are opposites. In a perfect world, you should be able to write that AB|D, but for a while I was chasing down mutual exclusion contradictions in Unicode properties — which I think I’ve tak...