reduce

I have an array containing 3 objects like so: class AClass { var distance: Int? } let obj0 = AClass() obj0.distance = 0 let obj1 = AClass() obj1.distance = 1 let obj2 = AClass() obj2.distance = 2 let arr = [obj0, obj1, obj2] When I reduce the array and assign it to a variable, I can only sum the last element in the array. let total = arr.reduce(0, {$1.distance! + $1.distance!}) //returns 4 If I try $0.distance! it errors with "expression is ambiguous without more context". I tried being more explicit: var total = arr.reduce(0, {(first: AClass, second: AClass) -> Int in return first.distance! +

This question already has answers here : Word Frequency Count, fix a bug with standard property (3 answers) Closed 5 years ago . I'm working through a tutorial on functional JS and I'm up to a challenge requiring the use of the reduce method: Given a random array of words, output an array that shows the word plus it's word count, for instance: ['apple, 'orange, 'grape', 'apple'] -> ['apple: 2','orange: 1', 'grape: 1] I know this isn't the correct use of reduce, but here was my semi-working solution: var wordCountsArray = inputWords.map(function(item){ var counter = 0; var itemCount =

my javascript Application works on firefox and chrome very well. But it seams to be broken on Internet Explorer (IE 8). I did not get an error Message on the console-log. By debugging the code I notice, that the application breaks on the following line: series.reduce(visit, []); The whole function exits at this point. I know, that reduce works for arrays, but console.info(typeof(series)) tells: object But this object exactly looks like an array - and it works on FF/Chrome. Could this be the reason, why IE stops processing the function at this point? And: how to handle this at IE? Thank you.

This is my JSON schema: {"emp_no": .., "salary": .., "from_date": .., "to_date": .., "type" : "salaries"} {"emp_no": .., "title": .., "from_date": .., "to_date" : .., "type" : "titles"} What i wanted to do, is to find the average salary for each active title. Active titles are document with "from_date" attribute set to "9999-01-01" Here is my Map Function function(doc) { if (doc.type == 'salaries') { var dateSalaries = null; dateSalaries = doc.to_date.split("-"); if(dateSalaries[0].localeCompare("9999") == 0){ emit(doc.emp_no, ["salary", doc.salary] ); } } else if (doc.type == 'titles') { var

The following code has no information that may lead it to run at CPU or GPU. I wonder where is the "reduce" operation executed? #include <thrust/iterator/counting_iterator.h> ... // create iterators thrust::counting_iterator<int> first(10); thrust::counting_iterator<int> last = first + 3; first[0] // returns 10 first[1] // returns 11 first[100] // returns 110 // sum of [first, last) thrust::reduce(first, last); // returns 33 (i.e. 10 + 11 + 12) Furthermore, thrust::transform_reduce( thrust::counting_iterator<unsigned int>(0), thrust::counting_iterator<unsigned int>(N), MyOperation(data), 0