c# Dictionary picking the key with the largest value

Question

I have a Dictionary<char, int> charstat to count occurrences of a character. I want to get the 5 most common character counts from this dictionary. How do go about doing this.

Some example data:

 <'T', 1>
 <'A', 2>
 <'C', 5>
 <'Q', 10>
 <'B', 3>
 <'Z', 7>

And from this I want to get in order of the largest count:

Q
Z
C
B
A

possible duplicate of [How do you sort a C# dictionary by value?](http://stackoverflow.com/questions/289/how-do-you-sort-a-c-sharp-dictionary-by-value) — Jonathon Reinhart, Jun 07 '13 at 07:29
By "5 most common character counts", do you mean the most common values, or the highest values? — Guffa, Jun 07 '13 at 07:33

score 5 · Accepted Answer · answered Jun 07 '13 at 07:29

5

I want to get the 5 most common character counts from this dictionary.

var item = charstat.OrderByDescending(r => r.Value)
                          .Select(r => r.Key)
                          .Take(5);

answered Jun 07 '13 at 07:29

Habib

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@Rawling Before editing code in question was invalid that was making this solution invalid as well. That might be a reason. +1 from me anyway. – Leri Jun 07 '13 at 07:36
1

@PLB, I didn't have `Select` clause, so it was originally selecting the dictionary item. now edited it to select the key. – Habib Jun 07 '13 at 07:42
Of course, if there's a tie, i.e. some values are equal, it is undefined which order these come in. – Jeppe Stig Nielsen Jun 07 '13 at 07:53

score 2 · Answer 2 · answered Jun 07 '13 at 07:31

  Dictionary<char, int> dir = new Dictionary<char, int>();
  // ...
  var query = (from p in dir
              orderby p.Value descending
              select p).Take(5);
  foreach (var item in query) {
    Console.Out.WriteLine("Char: {0}, Count: {1}", item.Key, item.Value);
  }

c# Dictionary picking the key with the largest value

2 Answers2