finding data from unique id in two tables

hi,

i have a two tables one is the master table with the following fields:

table a

unique id name age

j1 john 34

j2 max 18

j3 pablo 17

j4 immy 32

and so on consisting of around 100 rows

and the second table is just a column of unique ids but not in the same order as the master table for eg:

table b

unique id

j3

j2

around 40 rows ( number can change)

how do i extract data from table a using unique id from table b and fill the name and age column in table b?

i want the output of table b to be

unique id name age

j3 pablo 17

j2 max 18

do i have use a for loop only and check each unique id or is there a better and faster way?

any help on this matter would be highly appreciated.

thanks

Answer 1

[Rik]

You can use the ismember function.

[azim]

thanks. just to confirm then to fill i use the for loop

[Rik]

No need for any loops at all:

%Create the data
UID={'j1';'j2';'j3';'j4'};
name={'john';'max';'pablo';'immy'};
age=[34;18;17;32];
T1=table(UID,name,age);
UID={'j3';'j2'};
T2=table(UID);

%Find matches
[a,b]=ismember(T2.UID,T1.UID);

%Assign data
T2.name={T1.name{b}}.';
T2.age=T1.age(b);
T2

T2 = 2×3 table
     UID        name       age
    ______    _________    ___

    {'j3'}    {'pablo'}    17 
    {'j2'}    {'max'  }    18