How to fill arrays third column by matching first 2 columns

Dear all,

I have 2 arrays namely A & B.

A is 30 x 3 array with 3rd column zero.

B is 15 x 3 array with the result value in the 3rd column.

I want to fill the 3rd column of A by matching the first 2 columns with B.

for example,

A=[1 5 0;

1 12 0;

4 5 0;

4 9 0;

7 8 0;

8 2 0;

9 13 0];

B = [1 5 2740;

1 12 10;

8 2 1500;

7 8 750];

I want to get the array A's 3rd column filled with the values by comparing B.

results like,

A = [1 5 2740;

1 12 10;

4 5 0;

4 9 0;

7 8 750;

8 2 1500;

9 13 0];

Please suggest me a code for doing this for the larger size of array.

Thank you in advance.

Answer 1

[KSSV]

A=[1           5           0;
      1          12           0;
      4           5           0;
      4           9           0;
      7           8           0;
      8           2           0;
      9          13           0];
B = [1           5        2740;
        1          12          10;
        8          2        1500;
        7           8         750];
F = scatteredInterpolant(B(:,1),B(:,2),B(:,3)) ;
A(:,3) = F(A(:,1),A(:,2)) ;
A

A = 7×3

1.0e+03 * 0.0010 0.0050 2.7400 0.0010 0.0120 0.0100 0.0040 0.0050 1.9946 0.0040 0.0090 0.7700 0.0070 0.0080 0.7500 0.0080 0.0020 1.5000 0.0090 0.0130 -0.8471

[Muthukannan]

Thank you for the reply.

In this result, array index 2, 3, 4, 7 carries some other value that are not exist in array B. Since there are no value for these indices in B, I want keep the values in A as zero.

Please suggest.

Thank you.

[KSSV]

A=[1           5           0;
      1          12           0;
      4           5           0;
      4           9           0;
      7           8           0;
      8           2           0;
      9          13           0];
B = [1           5        2740;
        1          12          10;
        8          2        1500;
        7           8         750];
[c,ia] = ismember(B(:,1:2),A(:,1:2),'rows','legacy') ;
A(ia,3) = B(:,3)

A = 7×3

1 5 2740 1 12 10 4 5 0 4 9 0 7 8 750 8 2 1500 9 13 0

[Muthukannan]

Thank you so much. Its working.