matching vectors of different length

Hi

I kindly need some guidance for a problem as the one below. I am using a very large data set and perhaps the following description is the closest to the problem at hand

dates: A=[1 1 1 2 2 2 3 3 4 4 4 5 5 6 6 6]

Unique dates: B=[1 2 3 4 5 6]

Units corresponding to unique dates: C=[12 18 15 14 11 17]

Output : unit values in C corresponding to unique dates in B such as they match the order of dates appearing in A.

output= [12 12 12 18 18 18 15 15 14 14 14 11 11 17 17 17]

Thank you for any input

Answer 1

[Andrei Bobrov]

A = [1 1 1 2 2 2 3 3 4 4 4 5 5 6 6 6];
C=[12 18 15 14 11 17];
output= C(A);

e.g. [ EDIT 08:16MDT 13.12.2011 ]

A = randi([18 23],15,1)
[B B B] = unique(A)
C = randi(125,max(B),1)
output = C(B)

[Tiina]

Hi,

Thank you for your reply. I actually tried the same approach as in C(A) but I was getting an error message Index exceeds matrix dimension ..

The size of the vectors am using are

for A 60000x1 ; B 1511x1 ; C 1511x1

[Dr. Seis]

If your "A" matrix does not include numbers ranging from 1 : length(C), then you will most certainly get that error. Using the example above, if A = [11 11 11 12 12 12 13 13 14 14 14 15 15 16 16 16], then you could not simply do C(A) to obtain the desired result because there is no 11th, 12th, ..., 16th element - there are only 6 elements in C. You would have to us Andrei's line involving "UNIQUE" to obtain a vector with the appropriate numbers for indexing.

[Tiina]

Yea thank you it works with [B B B] I was doing [B].