Assigning values to vectors of different lenghts

Hello,

I've got three vectors, say a(1x4), b(1x4) and c(1x10). Vectors a and c represent the same thing, they are just codes. Vector b let's say it's my objective function.

a = [1 2 3 4]

b = [0.1 0.2 0.3 0.4]

c= [ 4 4 4 2 2 1 3 3 1 4].

I want to get another vector d, which will have the same dimensions as vector d (10x1) and in which the values of vector b will be assigned.

d should be like d = [0.4 0.4 0.4 0.2 0.2 0.1 0.3 0.3 0.1 0.4].

Any thoughts on this?

Many thanks

Answer 1

[Konstantinos Sofos]

Hi,

if your starting point is that you have a and c you can make d from b as

[~,idx] = ismember(c,a);
d = b(idx);

>> d

d =

      0.4000    0.4000    0.4000    0.2000    0.2000    0.1000    0.3000    0.3000    0.1000    0.4000

[Christina]

Good, it works!

Many thanks!

Answer 2

[Jon]

It's not clear what you need a for. You can make d directly from c and b as follows:

>> d=b(c)
d =
          0.4          0.4          0.4          0.2          0.2          0.1
          0.3          0.3          0.1          0.4