Find the top N ranked data in each group, where N is provided as a parameter. Name of the rank and the group are also provided as parameter.
Given the following data:[ { name: 'Tyler Bennett', id: 'E10297', salary: 32000, dept: 'D101' }, { name: 'John Rappl', id: 'E21437', salary: 47000, dept: 'D050' }, { name: 'George Woltman', id: 'E00127', salary: 53500, dept: 'D101' }, { name: 'Adam Smith', id: 'E63535', salary: 18000, dept: 'D202' }, { name: 'Claire Buckman', id: 'E39876', salary: 27800, dept: 'D202' }, { name: 'David McClellan', id: 'E04242', salary: 41500, dept: 'D101' }, { name: 'Rich Holcomb', id: 'E01234', salary: 49500, dept: 'D202' }, { name: 'Nathan Adams', id: 'E41298', salary: 21900, dept: 'D050' }, { name: 'Richard Potter', id: 'E43128', salary: 15900, dept: 'D101' }, { name: 'David Motsinger', id: 'E27002', salary: 19250, dept: 'D202' }, { name: 'Tim Sampair', id: 'E03033', salary: 27000, dept: 'D101' }, { name: 'Kim Arlich', id: 'E10001', salary: 57000, dept: 'D190' }, { name: 'Timothy Grove', id: 'E16398', salary: 29900, dept: 'D190' } ];one could rank top 10 employees in each department by calling
topRankPerGroup(10, data, 'dept', 'salary')
Given the following data:
[ { name: 'Friday 13th', genre: 'horror', rating: 9.9 }, { name: "Nightmare on Elm's Street", genre: 'horror', rating: 5.7 }, { name: 'Titanic', genre: 'drama', rating: 7.3 }, { name: 'Maze Runner', genre: 'scifi', rating: 7.1 }, { name: 'Blade runner', genre: 'scifi', rating: 8.9 } ];one could rank the top-rated movie in each genre by calling
topRankPerGroup(1, data, 'genre', 'rating')
topRankPerGroup
is a function.
testString: assert(typeof topRankPerGroup === 'function', 'topRankPerGroup
is a function.');
- text: topRankPerGroup
returns undefined on negative n values.
testString: assert(typeof topRankPerGroup(-1, []) === 'undefined', 'topRankPerGroup
returns undefined on negative n values.');
- text: First department must be D050
testString: assert.equal(res1[0][0].dept, 'D050', 'First department must be D050');
- text: First department must be D050
testString: assert.equal(res1[0][1].salary, 21900, 'First department must be D050');
- text: The last department must be D202
testString: assert.equal(res1[3][3].dept, 'D202', 'The last department must be D202');
- text: topRankPerGroup(1, ...)
must return only top ranking result per group.
testString: assert.equal(res2[2].length, 1, 'topRankPerGroup(1, ...)
must return only top ranking result per group.');
- text: topRankPerGroup(1, ...)
must return only top ranking result per group.
testString: assert.equal(res3[2][1].name, 'Maze Runner', 'topRankPerGroup(1, ...)
must return only top ranking result per group.');
```