How to get percentile in java

Question

I have a list where I want to get percentile.

HashMap<Integer,String> test=new HashMap<Integer,String>();  
test.put(100,"Amit");  
test.put(101,"Vijay");  
test.put(102,"Rahul"); 
test.put(103,"Amit");  
test.put(104,"Vijay");  
test.put(105,"Rahul");

Using following formula for percentile, how can I iterate and use properly? i want to get percentile of each keys in hash map

Number of scores blow X*100/N

not clear what you want ? explain in brief – Anand Dwivedi Jan 07 '16 at 09:57 — Anand Dwivedi, Jan 07 '16 at 09:57
i want to get percentile of each keys in hash map – Shakti Sharma Jan 07 '16 at 09:58 — Shakti Sharma, Jan 07 '16 at 09:58

ShadowPenguin · Answer 1 · 2016-01-07T10:09:25.297

0

So i haven worked that much with HashMaps, but looking at the JavaDoc it should be something like

Hashmap<Integer><String> h;
int sum = 0;
for(int i: h.keySet()) {
  sum += i;
}
double percentile = sum/h.size()

edited Jan 07 '16 at 10:09

answered Jan 07 '16 at 10:01

ShadowPenguin

106
1
9

i dont want key i awnt ot get percentile of ech key – Shakti Sharma Jan 07 '16 at 10:02
If i got that correct, then ure just looking for double perc = 1/h.size(); EDIT: nvm, ill Change my answer – ShadowPenguin Jan 07 '16 at 10:05

score 0 · Answer 2 · answered Jan 07 '16 at 10:27

You can do something like this (assuming by percentile you mean relative to the highest score what everyone scored, if you want distribution then you may want to use different computation but this should give you an idea)

    int maxScore = 0;
    for ( Integer score : test.keySet()) {
         if (score > maxScore) {
             maxScore = score;
         }
    }
    for ( Integer score : test.keySet()) {

         System.out.print(String.format("%s's percentile %5.2f\n", test.get(score), 
                 ((double)score/(double)maxScore)*100));
    }

Using the data you have you should get something as below

Rahul's percentile 97.14
Amit's percentile 98.10
Amit's percentile 95.24
Vijay's percentile 96.19
Vijay's percentile 99.05
Rahul's percentile 100.00

if i need to get based on value? – Shakti Sharma Jan 07 '16 at 10:57 — Shakti Sharma, Jan 07 '16 at 10:57

How to get percentile in java

2 Answers2