Array variables may not (yet) be exported. From the manpage of bash version 4.1.5 under ubuntu 10.04. The following statement from Chet Ramey (current bash maintainer as of 2011) is probably the most official documentation about this “bug”: There isn’t really a good way to encode an array variable into the environment. http://www.mail-archive.com/[email protected]/msg01774.html
You can use it like this: http://plnkr.co/edit/vtNjEgmpItqxX5fdwtPi?p=preview Like you found, filter accepts predicate function which accepts item by item from the array. So, you just have to create an predicate function based on the given criteria. In this example, criteriaMatch is a function which returns a predicate function which matches the given criteria. template: <div … Read more
With Bash version 4.3 and above, you can make use of a nameref so that the caller can pass in the array name and the callee can use a nameref to populate the named array, indirectly. #!/usr/bin/env bash create_array() { local -n arr=$1 # use nameref for indirection arr=(one “two three” four) } use_array() { … Read more
The idea is to treat the matrix as a series of layers, top-right layers and bottom-left layers. To print the matrix spirally we can peel layers from these matrix, print the peeled part and recursively call the print on the left over part. The recursion terminates when we don’t have any more layers to print. … Read more
Compute the discrete cumulative density function (CDF) of your list — or in simple terms the array of cumulative sums of the weights. Then generate a random number in the range between 0 and the sum of all weights (might be 1 in your case), do a binary search to find this random number in … Read more
See my answer about spatial and temporal locality. In particular, arrays are contiguous memory blocks, so large chunks of them will be loaded into the cache upon first access. This makes it comparatively quick to access future elements of the array. Linked lists on the other hand aren’t necessarily in contiguous blocks of memory, and … Read more
This is the easiest/shortest method I can find. Swift 3 and Swift 4: let multiples = […] let sum = multiples.reduce(0, +) print(“Sum of Array is : “, sum) Swift 2: let multiples = […] sum = multiples.reduce(0, combine: +) Some more info: This uses Array’s reduce method (documentation here), which allows you to “reduce … Read more
First two have the same effect. declare a variable array1_OfStrings, let it choose the type itself. When it sees [String](), it smartly knows that’s type array of string. You set the variable array2_OfStrings as type array of string, then you say it’s empty by [] This is different because you just tell you want array3_OfStrings … Read more
Why not use the built-in contains() function? It comes in two flavors func contains<S : SequenceType, L : BooleanType>(seq: S, predicate: @noescape (S.Generator.Element) -> L) -> Bool func contains<S : SequenceType where S.Generator.Element : Equatable>(seq: S, x: S.Generator.Element) -> Bool and the first one takes a predicate as argument. if contains(myArr, { $0.name == “Def” … Read more
If a procedure has a dummy argument that is an allocatable, then an explicit interface is required in any calling scope. (There are numerous things that require an explicit interface, an allocatable dummy is but one.) You can provide that explicit interface yourself by putting an interface block for your subroutine inside the main program. … Read more