summing tied (duplicate) numbers in a series

Greetings to all, I have a time series data e.g. [4 4 6 7 9 9 9 10 10 13 17 17 17] which is long. I need to identify tied values such that t1=3(three untied values (6, 7, 13)), t2=2 (two ties of extent two (4, 10)), t3=2 (two ties of extent three (9, 17)).

After performing this, I need to sum all the ties in the series using the following equation... ti[(ti-1)(2ti+5)] where ti denotes the magnitude of the tie.

Anyone with suggestion on how to go about this is welcome to help.

Thanks in advance.

Vincent

[Sean de Wolski]

Could you provide the output you expect for the above matrix?

It looks like (histc()||unique)+accumarray() will have a blast with this.

Answer 1

[Thomas]

this is a start:

a=[4 4 6 7 9 9 9 10 10 13 17 17 17];
b=unique(a);   % this shows unique values

c=find(diff(a)~=0)  % finds the differences in the values
d=[0 c length(a)];   % making new matrix to get the values

outputs=sortrows([b'  diff(d)'],2)

% follow this by summing your ties..

Answer 2

[Andrei Bobrov]

t = [4 4 6 7 9 9 9 10 10 13 17 17 17]
[a n n] = unique(t)
m = histc(n,1:max(n))
tout = accumarray(m',a',[],@(x){x})